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 A201241 #12 Apr 10 2020 02:18:05 %S A201241 0,0,0,16,4450,442980,11281312,139580160,1103589198,6433276500, %T A201241 30047250222,118507673088,408912072478,1265701033492,3579712962750, %U A201241 9380986518528,23027843919870,53409035159316,117860600410206,248890790976000,505371757001454,990655558290772 %N A201241 Number of ways to place 7 non-attacking wazirs on an n X n toroidal board. %C A201241 Wazir is a leaper [0,1]. %H A201241 V. Kotesovec, <a href="https://oeis.org/wiki/User:Vaclav_Kotesovec">Non-attacking chess pieces</a>, 6ed, p.402 %F A201241 a(n) = n^2*(n^12 - 105*n^10 + 4795*n^8 - 122115*n^6 + 1834084*n^4 - 15461460*n^2 + 57441600)/5040, n>=8. %F A201241 G.f.: -2*x^4 * (7*x^18 - 177*x^17 + 1965*x^16 - 12491*x^15 + 53736*x^14 - 175854*x^13 + 461641*x^12 - 942615*x^11 + 1320318*x^10 - 788656*x^9 - 1206129*x^8 + 3443471*x^7 - 3128600*x^6 - 552570*x^5 + 7435235*x^4 + 2548291*x^3 + 188955*x^2 + 2105*x + 8)/((x-1)^15). %Y A201241 Cf. A201236, A201237, A201238, A201239, A201240, A201242. %K A201241 nonn %O A201241 1,4 %A A201241 _Vaclav Kotesovec_, Nov 28 2011