This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A158029 #4 Jun 09 2016 21:44:49 %S A158029 1,2,4,5,7,8,22,23,27,28,32,33,37,77,84,91,98,105,112,119,126,133,140, %T A158029 521,529,531,539,541,549,551,559,561,569,571,579,581,589,591,599,601, %U A158029 609,611,619,621,629,631,639,641,649,651,659,661,669,671 %N A158029 Sides of squares which are filled exactly (no holes, no overlaps) by the digits needed to write a subsequence of consecutive square numbers, starting with 0. %C A158029 The square numbers fitting exactly in a "squares-digits square" are given by A158028. Terms computed by Jean-Marc Falcoz. %H A158029 Eric Angelini, <a href="http://www.cetteadressecomportecinquantesignes.com/DigitSpiral.htm">Digit Spiral</a> %H A158029 E. Angelini, <a href="/A158022/a158022.pdf">Digit Spiral</a> [Cached copy, with permission] %e A158029 ...0...01...0116...01161 %e A158029 .......49...4964...49640 %e A158029 ............2539...25390 %e A158029 ............6481...64811 %e A158029 ...................21144 %e A158029 The above squares, filled exactly by a subsequence of consecutive square numbers starting with 0 have sides 1, 2, 4, 5. There is no side-3 square with this property. The next properly filled square will have side 7. %K A158029 base,nonn %O A158029 1,2 %A A158029 _Eric Angelini_, Mar 11 2009