This is a list of obsoleted (but record-setting at the time) and/or alternative packings, shown alongside the corresponding best known. For the main list, see Squares in Squares.
Where the word "alternative" is used, this designates an alternative packing, which is enclosed within the same-sized bounding square as another packing, but cannot be reached by continuously translating and/or rotating the squares in that packing. When the packing can be reached by such continuous transformations, the word "rearrangement" is used.
Where a polynomial root is known for $s$ of degree $3$ or higher (and has no concise closed-form expression), a 🔒 icon is shown; click this to see the polynomial root form of $s$. For more information on each packing, view its SVG's source code.
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10.
$s = 3 + {1\over 2}\sqrt 2 = \Nn{3.70710678118654}$
Found by Frits Göbel
in early 1979.
Explore group
$s = 3 + {1\over 2}\sqrt 2 = \Nn{3.70710678118654}$
Alternative with minimal rotated squares.
Adds an "L" to $s(5)$.
11.
$s = {5\over 2}+\sqrt 2 = \Nn{3.91421356237309}$
Side length found by Frits Göbel
in early 1979.
$s = {5\over 2}+\sqrt 2 = \Nn{3.91421356237309}$
Side length found by Frits Göbel in early 1979.
Alternative with minimal rotated squares found by Charles F. Cottingham in 1979, documented by Martin Gardner in October 1979.
$s = 2 + {4\over 3}\sqrt 2 = \Nn{3.88561808316412}$
Found by Pertti Hämäläinen in 1980. Didn't set an overall record, but proved by Walter R. Stromquist in 2002 to be the optimal 45° packing.
$s = {}^{8}🔒 = \Nn{3.87708359002281}$
$s^8 - 20s^7 + 178s^6 - 842s^5 + 1923s^4 - 496s^3 - 6754s^2 + 12420s -6865 = 0$
Rigid.
Found by Walter Trump
in 1979.
17.
$s = 4 + {1\over 2}\sqrt 2 = \Nn{4.70710678118654}$
Found by Frits Göbel in early 1979.
Explore group
$s = 4 + {1\over 2}\sqrt 2 = \Nn{4.70710678118654}$
Alternative with minimal rotated squares.
Adds two "L"s to $s(5)$.
$s = {7\over 3} + {5\over 3}\sqrt 2 = \Nn{4.69035593728849}$
Found by Pertti Hämäläinen
in 1980.
$s = {}^{16}🔒 = \Nn{4.68012531131999}$
$2401s^{16}-100156s^{15}+1913156s^{14}-22179724s^{13}+174450876s^{12}-986379724s^{11}+4148847308s^{10}-13271035292s^9+32788723886s^8-63314062708s^7+96314291996s^6-115448677092s^5+107387254380s^4-74501848708s^3+35776185556s^2-10308876020s+1301040841=0$
Symmetric version found
by David W. Cantrell
in September 2023.
Possibly found by others previously.
Didn't set an overall record, but is the best known symmetric packing.
$s = {}^{18}🔒 = \Nn{4.67553009360455}$
$4775s^{18}-190430s^{17}+3501307s^{16}-39318012s^{15}+300416928s^{14}-1640654808s^{13}+6502333062s^{12}-18310153596s^{11}+32970034584s^{10}-18522084588s^9-93528282146s^8+350268230564s^7-662986732745s^6+808819596154s^5-660388959899s^4+358189195800s^3-126167814419s^2+26662976550s-2631254953=0$
Improved by John Bidwell
in 1998.
18.
$s = 2 + 2 \sqrt 2 = \Nn{4.82842712474619}$
Found by Frits Göbel
in early 1979.
Explore group
$s = 2 + 2 \sqrt 2 = \Nn{4.82842712474619}$
Rigid alternative found by David Ellsworth in December 2024.
$s = {7\over 2} + {1\over 2}\sqrt 7 = \Nn{4.82287565553229}$
Found by Pertti Hämäläinen
in 1980.
$s = {7\over 2} + {1\over 2}\sqrt 7 = \Nn{4.82287565553229}$
Alternative with minimal rotated squares found by Mats Gustafsson
in 1981.
$s = {7\over 2} + {1\over 2}\sqrt 7 = \Nn{4.82287565553229}$
Alternative found by David W. Cantrell
in September 2002.
$s = {7\over 2} + {1\over 2}\sqrt 7 = \Nn{4.82287565553229}$
Alternative found by Thierry Gensane and Philippe Ryckelynck
in 2004.
19.
$s = 4 +{2\over 3}\sqrt 2 = \Nn{4.94280904158206}$
Found by Frits Göbel
in early 1979.
$s = {7\over 2}+ \sqrt 2 = \Nn{4.91421356237309}$
Found by Charles F. Cottingham
in early 1979.
$s = {}^{4}🔒 = \Nn{4.88810889245683}$
$s^4-12s^3+51s^2-72s-36=0$
Found by Walter R. Stromquist
in 1984. Didn't set a record.
Fits the $s(n^2\!-\!n\!-\!1)$ pattern found by Joe DeVincentis in April 2014.
Explore group
$s = 3 +{4\over 3}\sqrt 2 = \Nn{4.88561808316412}$
Improved by Robert Wainwright
in late 1979.
(The first of many others to independently rediscover it that same year.)
$s = 3 +{4\over 3}\sqrt 2 = \Nn{4.88561808316412}$
Alternative packing found by
David W. Cantrell (see also min/max)
in 2002.
$s = 3 +{4\over 3}\sqrt 2 = \Nn{4.88561808316412}$
Alternative with minimal rotated squares found by David W. Cantrell
in 2002.
$s = 3 +{4\over 3}\sqrt 2 = \Nn{4.88561808316412}$
Alternative with minimal rotated squares found by David W. Cantrell (see also min)
in 2002.
27.
$s = 5 + {1\over 2}\sqrt 2 = \Nn{5.70710678118654}$
Found by Frits Göbel
in early 1979.
Explore group
$s = 5 + {1\over 2}\sqrt 2 = \Nn{5.70710678118654}$
Alternative with minimal rotated squares found by David W. Cantrell
in 2005.
28.
$s = 3 + 2 \sqrt 2 = \Nn{5.82842712474619}$
Found by Frits Göbel
in early 1979.
Explore group
$s = 3 + 2 \sqrt 2 = \Nn{5.82842712474619}$
Rigid alternative with minimal rotated squares found by David Ellsworth
in June 2023.
38.
$s = 6 + {1\over 2}\sqrt 2 = \Nn{6.70710678118654}$
Found by Frits Göbel
in early 1979.
Explore group
$s = 6 + {1\over 2}\sqrt 2 = \Nn{6.70710678118654}$
Alternative with minimal rotated squares found by David W. Cantrell
in 2005.
41.
$s = {11\over 3} + {7\over 3}\sqrt 2 = \Nn{6.96649831220388}$
Found by Evert Stenlund
in early 1980.
Didn't set a record.
$s = 2 + {7\over 2}\sqrt 2 = \Nn{6.94974746830583}$
Found by Charles F. Cottingham
in 1979.
$\begin{aligned}s &= 3 + {1\over 4}({7\sqrt 2 + \sqrt{46-8\sqrt 2}}) \\ &= \Nn{6.94725045864072}\end{aligned}$
$16s^4-192s^3+576s^2+112s-1471=0$
Found by David Cantrell
in October 2005.
$s = {}^{16}🔒 = \Nn{6.94614417648499}$
$128s^8-(4608-208\sqrt{2})s^7+(71872-6636\sqrt{2})s^6-(638064-89464\sqrt{2})s^5+(3555432-667296\sqrt{2})s^4-(12870448-3018620\sqrt{2})s^3+(29967224-8441484\sqrt{2})s^2-(41793736-13833116\sqrt{2})s+27410100-10616645\sqrt{2}=0$
$8192s^{16}-589824s^{15}+19773184s^{14}-410097792s^{13}+5896832880s^{12}-62424822464s^{11}+504125766080s^{10}-3174083848032s^9+15779426694720s^8-62284061030400s^7+195013700484408s^6-480451336747312s^5+915434726864080s^4-1307583226605576s^3+1324167214909432s^2-851847919501960s+262943639948975=0$
Improved by David Ellsworth
in November 2024.
Didn't set a record.
$s = {}^{4}🔒 = \Nn{6.93786550630255}$
$s^4-16s^3+95s^2-218s-34=0$
Found by Joe DeVincentis
in April 2014.
Fits an $s(n^2\!-\!n\!-\!1)$ pattern.
Explore group
52.
$s = 7 + {1\over 2}\sqrt 2 = \Nn{7.70710678118654}$
Found by Frits Göbel
in early 1979.
Explore group
$s = 7 + {1\over 2}\sqrt 2 = \Nn{7.70710678118654}$
Rigid alternative with minimal rotated squares found by David W. Cantrell
in 2005.
55.
$s = 8$
No nontrivial packing previously known.
$s = {}^{6}🔒 = \Nn{7.98701198965972}$
$481s^6-15166s^5+186713s^4-1132594s^3+3533776s^2-5430600s+3263162=0$
Found by David W. Cantrell
in August 2002.
$s = \Nn{7.9547901}$
Found by Joe DeVincentis
in April 2014.
Fits an $s(n^2\!-\!n\!-\!1)$ pattern.
Explore group
$s = \Nn{7.95424222760119}$
Improved by David Ellsworth
in June 2023.
$s = \Nn{7.95421084599443}$
Improved by David W. Cantrell
in August 2023.
$s = \Nn{7.95419161110664}$
Improved by David Ellsworth
in November 2024.
65.
$s = 5 + {5\over 2}\sqrt 2 = \Nn{8.53553390593273}$
Found by Frits Göbel
in early 1979.
Explore group
$s = 5 + {5\over 2}\sqrt 2 = \Nn{8.53553390593273}$
Rearrangement with minimal rotated squares found by David Ellsworth
in June 2023.
66.
$s = 3 + 4 \sqrt 2 = \Nn{8.65685424949238}$
Found by Evert Stenlund
in early 1980.
$s = 3 + 4 \sqrt 2 = \Nn{8.65685424949238}$
Alternative with rotational symmetry
found by David W. Cantrell
in 2023.
67.
$s = 8 + {5\over 7} = \Nn{8.71428571428571}$
Found by David Ellsworth
in December 2024.
Didn't set a record, but along with $s(104)$ is the first competitively-intended packing found with a rational side length. Its tilt angle is determined by the Pythagorean triple $\{3, 4, 5\}$.
$s = 8 + {1\over 2}\sqrt 2 = \Nn{8.70710678118654}$
Found by Evert Stenlund
in early 1980, extending the $s(52)$
found by Frits Göbel in early 1979.
Explore group
$s = 8 + {1\over 2}\sqrt 2 = \Nn{8.70710678118654}$
Alternative constructed by adding an "L" to the $s(52)$ found by Frits Göbel in early 1979.
$s = 8 + {1\over 2}\sqrt 2 = \Nn{8.70710678118654}$
Alternative with minimal rotated squares found by David W. Cantrell
in June 2023.
71.
71.
$s = 9$
No nontrivial packing previously known.
$s = {}^{8}🔒 = \Nn{8.96326750850139}$
$s^4-(18+10\sqrt{2})s^3+(157+152\sqrt{2})s^2-(746+742\sqrt{2})s+1353+1094\sqrt{2}=0$
$s^8-36s^7+438s^6-1064s^5-21677s^4+211944s^3-784922s^2+1228316s-563063=0$
Found by David Cantrell
in October 2005.
$s = {}^{4}🔒 = \Nn{8.96028765944389}$
$s^4-20s^3+151s^2-468s+12=0$
Found by Joe DeVincentis
in April 2014.
Fits an $s(n^2\!-\!n\!-\!1)$ pattern.
Explore group
84.
$s = 9 + {1\over 2}\sqrt 2 = \Nn{9.70710678118654}$
Found by Evert Stenlund
in early 1980, extending the $s(52)$
found by Frits Göbel in early 1979.
Explore group
$s = 9 + {1\over 2}\sqrt 2 = \Nn{9.70710678118654}$
Rearrangement. Can also be constructed by adding an "L" to the $s(67)$ that extends the $s(52)$ found by Frits Göbel in early 1979.
$s = 9 + {1\over 2}\sqrt 2 = \Nn{9.70710678118654}$
Alternative constructed by adding two "L"s to the $s(52)$ found by Frits Göbel in early 1979.
$s = 9 + {1\over 2}\sqrt 2 = \Nn{9.70710678118654}$
Alternative with minimal rotated squares found by David W. Cantrell
in 2005.
85.
$s = 2 + {11\over 2}\sqrt 2 = \Nn{9.77817459305202}$
Found by Evert Stenlund
in early 1980.
Extends the $s(18)$ found by
Frits Göbel in early 1979.
Explore group
$s = {11\over 2} + 3 \sqrt 2 = \Nn{9.74264068711928}$
Found by Erich Friedman
in 1997.
$s = {11\over 2} + 3 \sqrt 2 = \Nn{9.74264068711928}$
Alternative with minimal rotated squares.
89.
$s = 5 + {7\over 2}\sqrt 2 = \Nn{9.94974746830583}$
Found by Evert Stenlund in early 1980,
by extending a pattern found by Frits Göbel in early 1979.
Explore group
$s = 5 + {7\over 2}\sqrt 2 = \Nn{9.94974746830583}$
Rearrangement with minimal rotated squares found by David Ellsworth
in June 2023.
104.
$s = 10 + {5\over 7} = \Nn{10.71428571428571}$
Found by David Ellsworth
in December 2024.
Didn't set a record, but is the first competitively-intended packing found with a rational side length. Its tilt angle is determined by the Pythagorean triple $\{3, 4, 5\}$.
$s = 10 + {1\over 2}\sqrt 2 = \Nn{10.70710678118654}$
Extends the $s(52)$ found by
Frits Göbel in early 1979.
Explore group
$s = 10 + {1\over 2}\sqrt 2 = \Nn{10.70710678118654}$
simplified
109.
$s = {}^{4}🔒 = \Nn{10.97240394480333}$
$s^4-24s^3+219s^2-846s+126=0$
Continues the $s(n^2\!-\!n\!-\!1)$ pattern
found by Joe DeVincentis in April 2014,
but is not optimal.
Explore group
$s = 6 + {7\over 2}\sqrt 2 = \Nn{10.94974746830583}$
Extends a pattern found
by Frits Göbel in early 1979.
Explore group
131.
$s = \Nn{11.97614140898726}$
Found by Károly Hajba
in November 2024.
$s = \Nn{11.97350182495032}$
Found by David Ellsworth
in November 2024.
Fits an $s(n^2\!-\!n\!-\!1)$ pattern found
by Joe DeVincentis in April 2014.
Explore group
147.
148.
$ s = \tfrac{7}{2} + \tfrac{13}{2}\sqrt 2 = \Nn{12.69238815542511} $
Found by David Ellsworth in January 2025.
Provided for comparison.
$\begin{aligned}s &= \tfrac{7}{2} + \tfrac{ 1}{2}\sqrt{337} \\ &= \Nn{12.67877987534290}\end{aligned}$
Found by David Ellsworth in January 2025, based on the $s(293)$ improved by David W. Cantrell in January 2025.
Didn't set a record.
$ s = 7 + 4 \sqrt 2 = \Nn{12.65685424949238} $
Continues a pattern found
by Frits Göbel in early 1979.
Explore group
149.
$s = 12 + {1\over 2}\sqrt 2 = \Nn{12.70710678118654}$
Extends the $s(52)$ found by
Frits Göbel in early 1979.
Explore group
$s = 12 + {1\over 2}\sqrt 2 = \Nn{12.70710678118654}$
Rigid alternative with minimal rotated squares found by David Ellsworth in November 2024, based on the rigid $s(52)$ found by David W. Cantrell in 2005.
174.
$s = 13 + {5\over 7} = \Nn{13.71428571428571}$
Found by David Ellsworth
in December 2024.
Didn't set a record, but along with $s(104)$ is the first competitively-intended packing found with a rational side length. Its tilt angle is determined by the Pythagorean triple $\{3, 4, 5\}$.
$s = 13 + {1\over 2}\sqrt 2 = \Nn{13.70710678118654}$
Extends the $s(52)$ found by
Frits Göbel in early 1979.
Explore group
$s = 13 + {1\over 2}\sqrt 2 = \Nn{13.70710678118654}$
simplified
201.
$s = 14 + {5\over 7} = \Nn{14.71428571428571}$
Found by David Ellsworth
in December 2024.
Didn't set a record, but along with $s(104)$ is the first competitively-intended packing found with a rational side length. Its tilt angle is determined by the Pythagorean triple $\{3, 4, 5\}$.
$s = 14 + {1\over 2}\sqrt 2 = \Nn{14.70710678118654}$
Extends the $s(52)$ found by
Frits Göbel in early 1979.
Explore group
$s = 14 + {1\over 2}\sqrt 2 = \Nn{14.70710678118654}$
Mirror-symmetric alternative with minimal rotated squares arranged by David Ellsworth in December 2024, based on the technique found by David W. Cantrell in 2005.
$s = 14 + {1\over 2}\sqrt 2 = \Nn{14.70710678118654}$
Rotationally symmetric alternative with minimal rotated squares arranged by David W. Cantrell in December 2024.
$s = 14 + {1\over 2}\sqrt 2 = \Nn{14.70710678118654}$
Alternative combining the $s(52)$ rigid alternative with minimal rotated squares found by David W. Cantrell in 2005, and the $s(51)$ found by Károly Hajba
in July 2009.
202.
$s = {21\over 2} + 3 \sqrt 2 = \Nn{14.74264068711928}$
Found by David Ellsworth in November 2024, by extending the $s(85)$ found by Erich Friedman in 1997.
Didn't set a record.
$s = {}^{8}🔒 = \Nn{14.73657855744445}$
$776s^4-(33320+336\sqrt{2})s^3+(528568+7752\sqrt{2})s^2-(3662244+43296\sqrt{2})s+9301325-28968\sqrt{2}=0$
$6208s^8-533120s^7+19900352s^6-421620160s^5+5543230416s^4-46288934864s^3+239607688384s^2-702396496296s+891886272841=0$
Improved by David Ellsworth in November 2024, by adapting the $s(37)$ improvement found by
David W. Cantrell in September 2002.
Didn't set a record.
$s = {}^{4}🔒 = \Nn{14.73353239707125}$
$56s^4-1048s^3-16152s^2+457156s-2516321=0$
Improved by David Ellsworth
in January 2025.
Didn't set a record.
$s = 2 + 9 \sqrt 2 = \Nn{14.72792206135785}$
Extends the $s(18)$ found by
Frits Göbel in early 1979.
Explore group
209.
210.
209.
$s = {}^{4}🔒 = \Nn{14.98444916984191}$
$s^4-32s^3+391s^2-2082s+654=0$
Continues the $s(n^2\!-\!n\!-\!1)$ pattern
found by Joe DeVincentis in April 2014,
but is not optimal.
Explore group
$s = \Nn{14.98318264138415}$
Found by M.Z. Arslanov, S.A. Mustafin, and Z.K. Shangitbayev in March 2019.
Shows $s(n^2-n)<n$ for $n=15$.
$s = {}^{66}🔒 = \Nn{14.98264294789927}$
$1713850177070388831714241s^{66}-1036777957529676195922607870s^{65}+308070885285072811862199123417s^{64}-59939613454150601563431685241960s^{63}+8588813678023291261040553534326772s^{62}-966583568773741127569549391339079520s^{61}+88973510619748651618414859862026730876s^{60}-6888549315978477501144600760825939298456s^{59}+457813058489637019372876565898875762561962s^{58}-26525924226609242481987455544648574755740060s^{57}+1356297999041102109336083334683724973134359610s^{56}-61799914557147552310687442895919575623521766840s^{55}+2529586572366492011492859050137381026019860276228s^{54}-93635049365714878103413599709118844924967191715568s^{53}+3152090707330317380212505369273541211594578660668828s^{52}-96964556710709267169581794961613905049794026876686584s^{51}+2736977327538183203599671149196691182209406477480426999s^{50}-71141341918871267999443622612794042553629895963414923554s^{49}+1708099525395866416691912276683615496482061285927149098767s^{48}-37985865900286624496819504298337826100292397570681660970624s^{47}+784296971154264745366602352186813069922416329570936529960120s^{46}-15065885306353527422811618762658136922751746094197077043607808s^{45}+269749236797310845207931452385959355761508726043413698724913752s^{44}-4508953939245292278547355693056226796525821395294109220913219760s^{43}+70461706096440343504339359622207886316103484007784533453402451564s^{42}-1030684846592380569306994628265946835298274035988655898515756518536s^{41}+14127213285791424916401341828825119374306871082227591450747564708428s^{40}-181611012865775124333222503250168271689890578495810300493810490865200s^{39}+2191389437227659168703888781115852382017210534407970049772895556135144s^{38}-24835252575107480313771638509524748878675003716854534342036362523912096s^{37}+264493817830994381831108752939852505433266002142853663596745464038105112s^{36}-2648106506791820424837514470078773670571332661118776845107705934142835760s^{35}+24931817840154101718618675302330328982025705361265314835179979339556004095s^{34}-220774232592783180535637731350600608019775280385941635854721272379834520226s^{33}+1838859783489983364796248010427404448952293664994580697429468489690817448391s^{32}-14405793276814386692861915917557813798574320839280787544681770605702716243496s^{31}+106132652991766969969790599313795738256162256172065649640195937493783785627012s^{30}-735141103620029965659773734189613183265405874983552791121595763935147775210784s^{29}+4785629939469775130214760518204470967279654407141021153131677479220692014706252s^{28}-29264396180717787590970697217467423077531807932966908615153820237900145532452792s^{27}+167997715129752800946484031210802390736511802747887658272905155103288606648529418s^{26}-904700154474475752208581796921737926689902979381082659180178913034340167719783580s^{25}+4566216117618812719619282953953565095633492925168145038704985120782850946704225818s^{24}-21577735591142156619368360651289725338415069076557628274035844600998082681026841624s^{23}+95351638011084223101955380792874473279508189366232625045913569058491535016623736724s^{22}-393477264331394419045246438963291356261882874125326625922439475690536334420518557680s^{21}+1513871326020646900995786895290089433666501518786395002635104303984667876045713548492s^{20}-5420589319604280486120080489351603688574661016232355428256686514216840385980014845144s^{19}+18025671901154216272856257915455921861722569907273247804240829505876591992203422527785s^{18}-55538726517617123321306980401388416698101944528011997777048904298548850658621880672382s^{17}+158119388173030536226827428726717197786937874399240446800307626931688853687437117891505s^{16}-414679766978138921331059461345942561913790083283653894727325899938505427858892965125872s^{15}+998228943688800328823203749490058494562116495933106174279441691815211346156075844428112s^{14}-2196572339864925849617348696491086772493215350378298856026223386996595289374884651752448s^{13}+4397165113585946993607002307549324635278671461053934532945038939803841295777334091620192s^{12}-7962739349659864081806356456004225116652369166110620089333680683881143975151724678690048s^{11}+12957137888727586584941034560243767737163859971700725359751881246527790566047851156973568s^{10}-18794133216992559109409136095289044747144304027555381568607235733444082266478813293896192s^9+24062707252931451750084904210379578567640678822720136431418887027294986269907390293532928s^8-26864643906507885513435835499475292614570149380412717542767363827389611363117057750564864s^7+25750555425531123093287716207567520607853292058501569356839679301847154190381313748566016s^6-20763167580966447999929009292788490161886160932306769296176687436564687869505524614365184s^5+13694576920953853335160219343243224031929703522356095792630808590038480485959704606801920s^4-7094101031359142126885338736264230663456345418028425142721873216376995826523389107896320s^3+2706320051143905447935556673344831161461373449684695751208915990592616770507314550538240s^2-675931907390084983300050927121665770468081954992407462935298185140040600624082498617344s+82905798822484597710700208785408047898314652058813563312936555293758738816713843802112=0$
Improved by David Ellsworth
in December 2024.
$s = \Nn{14.96442179744201}$
Found by David Ellsworth in December 2024, by removing 1 square from the $s(210)$ found by M.Z. Arslanov, S.A. Mustafin, and Z.K. Shangitbayev in March 2019 and improved by David Ellsworth in December 2024.
271.
272.
$s = {}^{4}🔒 = \Nn{16.98770404979942}$
$s^4-36s^3+495s^2-2988s+1116=0$
Continues the $s(n^2\!-\!n\!-\!1)$ pattern
found by Joe DeVincentis in April 2014,
but is not optimal.
Explore group
$s = \Nn{16.98470216018343}$
Adds an "L" to the $s(240)$ found by Károly Hajba in September 2015.
$s = \Nn{16.98318264138415}$
Adds an "L" to the $s(240)$ based on the $s(210)$ found by M.Z. Arslanov, S.A. Mustafin, and Z.K. Shangitbayev in March 2019.
$s = \Nn{16.98318264138415}$
Based on the $s(210)$ found by M.Z. Arslanov, S.A. Mustafin, and Z.K. Shangitbayev in March 2019.
$s = {}^{66}🔒 = \Nn{16.98264294789927}$
$1713850177070388831714241s^{66}-1263006180902967521708887682s^{65}+457556854283194653508246334297s^{64}-108626085650108755375383219863016s^{63}+19007543579258154993013605104517540s^{62}-2614249620222774694075991845075567408s^{61}+294320445544799712214422954346585080428s^{60}-27891472736856262183567432641837740604344s^{59}+2270607650860185114208141699776485160991834s^{58}-161270542469096575205017999202879333703379396s^{57}+10115431614750251067098547571363673856667344506s^{56}-565808816641730403858512432034552952494802469080s^{55}+28450183984319404845113532374059123476095944389108s^{54}-1294559647452187836265838445107719695018437168558336s^{53}+53606558683243577767537060160465091965389251586245100s^{52}-2029777274949400008320972989373569605256603237798407896s^{51}+70566124724622022053181378677212143452798761833741049255s^{50}-2260494118677599144499162628207117877734197301937499627454s^{49}+66928391584632217881721045867244937443110647589022537806159s^{48}-1836487293516144718606242405600092685339691196348395055392352s^{47}+46812433957159983606351028994995744914840143394813517611414488s^{46}-1110784325503673809119053441923324973802716059719307513683034144s^{45}+24580067642598124655873296327812538035270416503768622579007969464s^{44}-508058601195291180778593698054098715271789503226858668644025004528s^{43}+9822636844453945473008973446300398331806350662367666559112039098828s^{42}-177850157754818541348101942178417197242325906137100400008326274953784s^{41}+3018908592957234274621453725329581711584511453209430776141062678498508s^{40}-48084823616106717807937793455351705691203975334728299955852985477677936s^{39}+719219081331785321193765357384648827974404178174478952936526177053613640s^{38}-10108484874977669848442591400277761623042675059618304149046369427119689280s^{37}+133569141781888512562398911029947506237982901071358900752904689441632946104s^{36}-1659947237436600687047903428474338638444186680114020006663182877218281431536s^{35}+19407721788005616167841988847134491979124178917074454947061592816288392155103s^{34}-213512563646549268743663877471869657452486579360256542887702449445267477625758s^{33}+2210398398130635465592076383059864672001655782088693299537565902349619712869319s^{32}-21532723313632709226861394724764610661805015535470154323486739829302573530834280s^{31}+197353488882411915369080553242112202824443643000941071851504553934557696342479860s^{30}-1701361607748327036898500039362885770951773534397536787240248737455726000275481776s^{29}+13790944656640719079864365329065256075236685711621827154509298129212864382169075708s^{28}-105057191253365590055038856706594446361850240187411125808555225806066647805699033432s^{27}+751670513866794149869446078936059679095796755093931999846310783101254874128343844858s^{26}-5047524051032968924904168688747563678450991211248789313855857351391502072525065835844s^{25}+31783178768787466515646386129275724683780750656572320239619905303340921614133673928026s^{24}-187472727052955447696160431653518028007026362437178333588607245141115925448495562239416s^{23}+1034626229621705034003065868277725184320524563387572538925459708898162378122695884371524s^{22}-5335045699393078934531764329130636548870723955424210927081461414593591826916976872572736s^{21}+25663737575409659302307158237342619977251070651367656518135022159442843909863332058148316s^{20}-114960649295229282113311852806854796874367423592350138710159368893751322473994310949804856s^{19}+478559753673706084748519492363770439999236334487313334845093021068854656585876271428583577s^{18}-1846990700033721376192730686948971722144142619617398680320187325046521383970748784637316834s^{17}+6591326456994561029578640106261265890282504157582308701300923406400578110653255439076001265s^{16}-21683429758094255971784837646080964873309338986609460623022430958540451763873664347265934416s^{15}+65523328529399452484083881848848270952170741513603155833639414320711386575541360843917428752s^{14}-181134395473848110073827498749917703659200447864218040383057641661298047344658812692009492864s^{13}+455904206381436590247441608773490326831830404955375957062019998388748856279690733152466535776s^{12}-1038920953582196812525580854613110667241159361649685005599580196703726210365369892962261589248s^{11}+2129321555265993058808909413739742507947670301867618671926711075672095702442458870941704884224s^{10}-3893858393082444876460677140167356642408686917745920213899715750218779803640863536637271852544s^9+6291634657144980094912045673643258772753140381469197256391134629731334665393467914754165776640s^8-8874016200990822056453884612581892989147523385532622735339375442773419838200440294959402524672s^7+10757961171340950446264308166124992160748835994596014475038180685505768156638580567927181983744s^6-10983792379878536403573363876927768332193956898933674258258398402852665358347513825072163651584s^5+9184651747912342152838771898129517117129618056068600195075502388329608767166607606008661409792s^4-6040013853226973048374847053430821660325834738741764444484502435456762249243146187494035292160s^3+2929211695042187145319679151141672508929021947850940754766129715898448812797031858745271910400s^2-931421152741943199632685430128893095342601525238972381704891083745166622082394765118220009472s+145672913717139262806845359990077919840464280273804604430606108170184726692142354311210336256=0$
Improved by David Ellsworth
in December 2024.
272.
$s = 17$
No nontrivial packing previously known.
$s < 17$
Found by Lars Cleemann
between 1991 and 1998.
Bounded the $s(n^2-n)=n$ conjecture to $n \lt 17$.
$s = {}^{5}🔒 = \Nn{16.99151646824600}$
$s^5-49s^4+872s^3-6894s^2+24437s-34521=0$
Local optimum squeeze found by
David Ellsworth in May 2023.
$s = {}^{4}🔒 = \Nn{16.98786575951164}$
$10s^4-470s^3+7840s^2-54504s+134721=0$
Improved by Károly Hajba
in September 2015.
(see also max staggering angle)
$s = \Nn{16.98318264138415}$
Based on the $s(210)$ found by M.Z. Arslanov, S.A. Mustafin, and Z.K. Shangitbayev in March 2019.
$s = {}^{66}🔒 = \Nn{16.98264294789927}$
$1713850177070388831714241s^{66}-1263006180902967521708887682s^{65}+457556854283194653508246334297s^{64}-108626085650108755375383219863016s^{63}+19007543579258154993013605104517540s^{62}-2614249620222774694075991845075567408s^{61}+294320445544799712214422954346585080428s^{60}-27891472736856262183567432641837740604344s^{59}+2270607650860185114208141699776485160991834s^{58}-161270542469096575205017999202879333703379396s^{57}+10115431614750251067098547571363673856667344506s^{56}-565808816641730403858512432034552952494802469080s^{55}+28450183984319404845113532374059123476095944389108s^{54}-1294559647452187836265838445107719695018437168558336s^{53}+53606558683243577767537060160465091965389251586245100s^{52}-2029777274949400008320972989373569605256603237798407896s^{51}+70566124724622022053181378677212143452798761833741049255s^{50}-2260494118677599144499162628207117877734197301937499627454s^{49}+66928391584632217881721045867244937443110647589022537806159s^{48}-1836487293516144718606242405600092685339691196348395055392352s^{47}+46812433957159983606351028994995744914840143394813517611414488s^{46}-1110784325503673809119053441923324973802716059719307513683034144s^{45}+24580067642598124655873296327812538035270416503768622579007969464s^{44}-508058601195291180778593698054098715271789503226858668644025004528s^{43}+9822636844453945473008973446300398331806350662367666559112039098828s^{42}-177850157754818541348101942178417197242325906137100400008326274953784s^{41}+3018908592957234274621453725329581711584511453209430776141062678498508s^{40}-48084823616106717807937793455351705691203975334728299955852985477677936s^{39}+719219081331785321193765357384648827974404178174478952936526177053613640s^{38}-10108484874977669848442591400277761623042675059618304149046369427119689280s^{37}+133569141781888512562398911029947506237982901071358900752904689441632946104s^{36}-1659947237436600687047903428474338638444186680114020006663182877218281431536s^{35}+19407721788005616167841988847134491979124178917074454947061592816288392155103s^{34}-213512563646549268743663877471869657452486579360256542887702449445267477625758s^{33}+2210398398130635465592076383059864672001655782088693299537565902349619712869319s^{32}-21532723313632709226861394724764610661805015535470154323486739829302573530834280s^{31}+197353488882411915369080553242112202824443643000941071851504553934557696342479860s^{30}-1701361607748327036898500039362885770951773534397536787240248737455726000275481776s^{29}+13790944656640719079864365329065256075236685711621827154509298129212864382169075708s^{28}-105057191253365590055038856706594446361850240187411125808555225806066647805699033432s^{27}+751670513866794149869446078936059679095796755093931999846310783101254874128343844858s^{26}-5047524051032968924904168688747563678450991211248789313855857351391502072525065835844s^{25}+31783178768787466515646386129275724683780750656572320239619905303340921614133673928026s^{24}-187472727052955447696160431653518028007026362437178333588607245141115925448495562239416s^{23}+1034626229621705034003065868277725184320524563387572538925459708898162378122695884371524s^{22}-5335045699393078934531764329130636548870723955424210927081461414593591826916976872572736s^{21}+25663737575409659302307158237342619977251070651367656518135022159442843909863332058148316s^{20}-114960649295229282113311852806854796874367423592350138710159368893751322473994310949804856s^{19}+478559753673706084748519492363770439999236334487313334845093021068854656585876271428583577s^{18}-1846990700033721376192730686948971722144142619617398680320187325046521383970748784637316834s^{17}+6591326456994561029578640106261265890282504157582308701300923406400578110653255439076001265s^{16}-21683429758094255971784837646080964873309338986609460623022430958540451763873664347265934416s^{15}+65523328529399452484083881848848270952170741513603155833639414320711386575541360843917428752s^{14}-181134395473848110073827498749917703659200447864218040383057641661298047344658812692009492864s^{13}+455904206381436590247441608773490326831830404955375957062019998388748856279690733152466535776s^{12}-1038920953582196812525580854613110667241159361649685005599580196703726210365369892962261589248s^{11}+2129321555265993058808909413739742507947670301867618671926711075672095702442458870941704884224s^{10}-3893858393082444876460677140167356642408686917745920213899715750218779803640863536637271852544s^9+6291634657144980094912045673643258772753140381469197256391134629731334665393467914754165776640s^8-8874016200990822056453884612581892989147523385532622735339375442773419838200440294959402524672s^7+10757961171340950446264308166124992160748835994596014475038180685505768156638580567927181983744s^6-10983792379878536403573363876927768332193956898933674258258398402852665358347513825072163651584s^5+9184651747912342152838771898129517117129618056068600195075502388329608767166607606008661409792s^4-6040013853226973048374847053430821660325834738741764444484502435456762249243146187494035292160s^3+2929211695042187145319679151141672508929021947850940754766129715898448812797031858745271910400s^2-931421152741943199632685430128893095342601525238972381704891083745166622082394765118220009472s+145672913717139262806845359990077919840464280273804604430606108170184726692142354311210336256=0$
Improved by David Ellsworth
in December 2024.
296.
$s = 17 + {1\over 2}\sqrt 2 = \Nn{17.70710678118654}$
Extends the $s(52)$ found by
Frits Göbel in early 1979.
Explore group
$s = 17 + {1\over 2}\sqrt 2 = \Nn{17.70710678118654}$
Rigid alternative with minimal rotated squares, based on the rigid $s(52)$ found by David W. Cantrell in 2005.
1765.
$s = {}^{4}🔒 = \Nn{42.49171522113325}$
$229s^4-13040s^3-12743s^2+4396114s+90109052=0$
Found by Károly Hajba
in November 2024.
Bounds $\{s(n^2\!+\!1)\} \ge {1\over 2}$ to $n \lt 42$.
Beats the $s(1765)$ Göbel square.
$s = {}^{4}🔒 = \Nn{42.49171522113325}$
$229s^4-13040s^3-12743s^2+4396114s+90109052=0$
Rearranged for comparison with subsequent improvement.
$s = {}^{4}🔒 = \Nn{42.48797851186022}$
$2s^4-212s^3+8129s^2-148140s+1362276=0$
Improved by David Ellsworth
in November 2024.
For more details, see Erich Friedman's paper on the subject: Packing Unit Squares in Squares: A Survey and New Results (or David Ellsworth's edit).