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 A126648 #17 Jan 27 2019 09:03:59 %S A126648 71,1,51,21,41,61,31,81,11 %N A126648 A 3 X 3 magic square with magic sum 123 and entries congruent to 1 (mod 10): equals 10*A033812 - 9. %C A126648 The magic sum is 123. See Figure C.4 in Appendix C in Maya Ahmed's PhD thesis. %H A126648 Maya Mohsin Ahmed, <a href="http://arXiv.org/abs/math/0405476">Algebraic Combinatorics of Magic Squares</a>, arXiv:math/0405476 [math.CO], 2004. PhD thesis. %H A126648 Maya Mohsin Ahmed, <a href="http://www.jstor.org/stable/4145267">How many squares are there, Mr. Franklin?: Constructing and Enumerating Franklin Squares</a>, Amer. Math. Monthly, Vol. 111, 2004, pp. 394-410 %H A126648 <a href="/index/Mag#magic">Index entries for sequences related to magic squares</a> %F A126648 a(n) = 10*A033812(n) - 9. - _M. F. Hasler_, Jan 26 2019 %e A126648 The magic square is: %e A126648 71 1 51 %e A126648 21 41 61 %e A126648 31 81 11 %Y A126648 Cf. A033812. %K A126648 fini,full,nonn,tabf %O A126648 1,1 %A A126648 _Parthasarathy Nambi_, Feb 08 2007 %E A126648 Edited by _M. F. Hasler_, Jan 26 2019