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 A271103 #59 Jun 02 2024 12:58:22 %S A271103 1,0,9,68688,579043051200,94590660245399996601600 %N A271103 Number of magic and semi-magic squares of order n composed of the numbers from 1 to n^2, counted up to rotations and reflections. %C A271103 A semi-magic square differs from a magic square in that at least one of its main diagonals does not sum to the magic constant. [_Walter Trump_] %C A271103 The number of order 4 magic and semi-magic squares was computed by Mutsumi Suzuki, and could be found on his former web site. Mutsumi Suzuki's pages are now in the Internet Archive. %C A271103 The number of order 5 magic and semi-magic squares was computed by _Walter Trump_ in March 2000. %C A271103 The number of order 6 magic and semi-magic squares was calculated by Artem Ripatti in April 2018, and published in his paper dated July 10, 2018. - _William Walkington_, Jul 17 2018 %H A271103 Artem Ripatti, <a href="https://arxiv.org/abs/1807.02983">On the number of semi-magic squares of order 6</a>, arXiv:1807.02983 [math.CO], 2018. See Table 1 p. 2. %H A271103 Mutsumi Suzuki, <a href="https://web.archive.org/web/20011115233406/http://www.pse.che.tohoku.ac.jp/~msuzuki/MagicSquare.4x4.semi.html">Semi-Magic Squares of 4 x 4</a>, first "captured" by the Internet Archive on the 5th October 1999. %H A271103 Walter Trump, <a href="http://www.trump.de/magic-squares/howmany.html">How many magic squares are there? - Results of historical and computer enumeration</a>. %H A271103 <a href="/index/Mag#magic">Index entries for sequences related to magic squares</a> %F A271103 a(n) = A271104(n)* n^2. %Y A271103 Cf. A006052, A270876, A271104. %K A271103 nonn,more %O A271103 1,3 %A A271103 _William Walkington_, Mar 30 2016 %E A271103 a(6) added by _William Walkington_, Jul 17 2018