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 A177757 #17 Nov 05 2016 11:07:56
%S A177757 0,0,0,64,600,6912,29400,132864,381024,1139200,2613600,6177600,
%T A177757 12269400,24912384,44717400,81636352,135945600,229423104,360561024,
%U A177757 572788800,859685400,1301766400,1881864600,2740725504,3840540000
%N A177757 Number of ways to place 4 nonattacking bishops on an n X n toroidal board.
%H A177757 Vincenzo Librandi, <a href="/A177757/b177757.txt">Table of n, a(n) for n = 1..1000</a>
%H A177757 V. Kotesovec, <a href="https://oeis.org/wiki/User:Vaclav_Kotesovec">Non-attacking chess pieces</a>, 6ed, 2013
%H A177757 <a href="/index/Rec#order_16">Index entries for linear recurrences with constant coefficients</a>, signature (2,6,-14,-14,42,14,-70,0,70,-14,-42,14,14,-6,-2,1).
%F A177757 a(n) = 1/48*(n-2)^2*n^2*(2n^4 -16n^3 +50n^2 -84n +81 +(6n^2 -36n +63)*(-1)^n).
%F A177757 G.f.: -8x^4*(3x^11 +122x^10 +401x^9 +2508x^8 +3316x^7 +7780x^6 +5172x^5 +5236x^4 +1609x^3 +666x^2 +59x+8)/((x-1)^9*(x+1)^7).
%t A177757 CoefficientList[Series[- 8 x^3 (3 x^11 + 122 x^10 + 401 x^9 + 2508 x^8 + 3316 x^7 + 7780 x^6 + 5172 x^5 + 5236 x^4 + 1609 x^3 + 666 x^2 + 59 x + 8)/((x - 1)^9 (x + 1)^7), {x, 0, 50}], x] (* _Vincenzo Librandi_, May 31 2013 *)
%t A177757 LinearRecurrence[{2,6,-14,-14,42,14,-70,0,70,-14,-42,14,14,-6,-2,1},{0,0,0,64,600,6912,29400,132864,381024,1139200,2613600,6177600,12269400,24912384,44717400,81636352},50] (* _Harvey P. Dale_, Nov 05 2016 *)
%Y A177757 Cf. A172127, A177755, A177756.
%K A177757 nonn,easy
%O A177757 1,4
%A A177757 _Vaclav Kotesovec_, May 13 2010