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 A096660 #12 Dec 27 2018 13:46:26 %S A096660 223,593,811,6113,15319,22123,22409,22817,24859,32801,40013,43853, %T A096660 47599,48259,51329,56383,64553,64579,77813,96401,109169,109937,135607, %U A096660 191899,229507,254623,281609,379157,496963,526963,530753,700781,1090373 %N A096660 Primes p such that the p-1 digits of the ternary (base 3) expansion of k/p (for k=1,2,3,...,p-1) fit into the k-th row of a magic square grid of order p-1. %D A096660 W. S. Andrews, Magic Squares and Cubes, pp. 176 Dover NY 1960. %D A096660 J. Heleen, Journal of Recreational Mathematics, 30(1) 1999-2000 pp. 72-3 Soln. to Prob. 2394. Magic Reciprocals %D A096660 M. J. Zerger, Journal of Recreational Mathematics, 30(2) 1999-2000 pp. 158-160 Soln. to Prob. 2420. Only 19? %H A096660 H. Heinz <a href="http://www.magic-squares.net/magic_squares_index.htm">Order 18 based on 1/19</a> %H A096660 Simon Whitechapel <a href="https://web.archive.org/web/20080518020634/http://www.gwywyr.com/articles/scimaths/pseudo.html">Reciprocal Arrangements</a> [Internet Archive Wayback Machine] %Y A096660 Cf. A072359, A096339. %K A096660 nonn,base %O A096660 1,1 %A A096660 Simon Whitechapel (aladgyma(AT)yahoo.com), Jul 02 2004 %E A096660 Corrected and extended by _William Rex Marshall_, Aug 18 2005 %E A096660 Corrected by _T. D. Noe_, Nov 15 2006