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 A161359 #5 Mar 31 2012 12:35:30 %S A161359 0,1,3,4,4,6,8,7,9,10,10,12,12,14,15,16,18,17,21,20,21,23,22,24,24,28, %T A161359 27,28,31,30,32,31,33,36,35,36,40,39,38,40,40,42,45,44,45,45,49,48,50, %U A161359 49,53,52,52,54,55,56,60,59,58,60,60,64,63,66,65,66,68,67,71,70,72,71 %N A161359 Number of squares in inner rectangle described in A168339. %F A161359 a(n) = A168339(n) - 2*(A161357(n)+A161358(n)) - 4. %Y A161359 Cf. A168339, A161369. %K A161359 nonn %O A161359 1,3 %A A161359 _R. H. Hardin_ and _N. J. A. Sloane_, Nov 27 2009 %E A161359 More terms (variables cost-2*(dimm+dimn)-4 of the C program in A168339) added by _R. J. Mathar_, Mar 06 2010