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 A225997 #8 Sep 06 2013 02:02:54 %S A225997 231,1724086,23850799560,182201755171800,1431877318884329856, %T A225997 13044657178246280571712,116927857061958334999652864, %U A225997 1034834452512042254405345443200,9329147292031736106743104217184000 %N A225997 Number of pairs of orthogonal (-1,6) vectors of length 7*n. %C A225997 Row 11 of A225987. %H A225997 R. H. Hardin, <a href="/A225997/b225997.txt">Table of n, a(n) for n = 1..67</a> %e A225997 Some solutions for n=1 %e A225997 .-1..6...-1..6...-1..6...-1.-1....6..6...-1..6...-1..6...-1..6...-1..6...-1..6 %e A225997 ..6..6....6.-1...-1..6...-1.-1...-1..6...-1..6...-1..6...-1..6....6.-1....6.-1 %e A225997 .-1..6....6.-1....6..6...-1.-1...-1..6....6.-1...-1..6....6..6....6..6...-1..6 %e A225997 ..6.-1...-1..6....6.-1...-1..6....6.-1....6..6....6..6...-1..6...-1..6...-1..6 %e A225997 ..6.-1...-1..6....6.-1...-1.-1...-1..6...-1..6....6.-1...-1..6...-1..6...-1..6 %e A225997 ..6.-1....6..6....6.-1...-1.-1....6.-1...-1..6....6.-1....6.-1...-1..6....6..6 %e A225997 ..6.-1...-1..6....6.-1...-1.-1...-1..6...-1..6....6.-1....6.-1...-1..6....6.-1 %K A225997 nonn %O A225997 1,1 %A A225997 _R. H. Hardin_, May 22 2013