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 A125006 #3 Mar 31 2012 14:45:33 %S A125006 15,18,21,24,27,30,33,34,36,38,39,42,45,46,48,50,51,54,57,58,60,62,63, %T A125006 65,66,69,70,72,74,75,78,80,81,82,84,85,86,87,90,93,94,95,96,98,99, %U A125006 100,102,105,106,108,110,111,114,115,117,118,120,122,123,125,126,129,130 %N A125006 Numbers n for which nontrivial positive magic squares with magic sum n exist. For a definition of nontrivial positive magic squares, see A125005. %C A125006 This sequence lists all values s such that A125005(s) > 0. %e A125006 a(1) = 15 because 15 is the smallest integer s for which a nontrivial positive magic square with magic sum s exists. %Y A125006 Cf. A125005, A125007, A125008, A125009, A125010, A125011, A125012, A125013, A125014, A125015, A125016, A125017. %K A125006 easy,nonn %O A125006 1,1 %A A125006 _Jens Voß_, Nov 15 2006