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 A187194 #13 Apr 19 2022 07:38:25 %S A187194 0,0,2304,156672,2169600,15220800,72182880,264520704,806827392, %T A187194 2144534400,5120913600,11222069760 %N A187194 Number of 7-turn rook's tours on an n X n board summed over all starting positions. %F A187194 Empirical G.f.: -96*x^3*(287*x^5+4491*x^4+11886*x^3+8776*x^2+1416*x+24)/(x-1)^9. [_Colin Barker_, Jul 01 2012] %e A187194 Some solutions for 3X3 %e A187194 ..2..1..0....1..2..0....0..2..1....0..0..4....5..4..0....4..3..5....4..1..5 %e A187194 ..3..6..7....6..0..7....5..3..4....1..2..3....6..0..7....7..1..6....0..7..6 %e A187194 ..4..5..0....5..3..4....6..0..7....7..6..5....2..3..1....0..2..0....3..2..0 %Y A187194 Row 7 of A187189. %K A187194 nonn,more %O A187194 1,3 %A A187194 _R. H. Hardin_, Mar 06 2011