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 A143081 #3 Oct 12 2012 14:54:52
%S A143081 -1,1,1,1,3,1,3,15,15,3,15,105,175,105,15,105,945,2205,2205,945,105,
%T A143081 945,10395,31185,43659,31185,10395,945,10395,135135,495495,891891,
%U A143081 891891,495495,135135,10395,135135,2027025,8783775,19324305,24845535,19324305,8783775,2027025,135135,2027025,34459425
%N A143081 A symmetrical triangle of coefficients based on A001147: a(n)=(2*n-1)*a(n-1); t(n,m)=a(n)^2/((2*n - 1)*a(m)*a(n - m)).
%C A143081 Row sums are:{-1, 2, 5, 36, 415, 6510, 128709, 3065832, 85386015, 2721425850, 97665121125}.
%F A143081 a(n)=(2*n-1)*a(n-1); t(n,m)=a(n)^2/((2*n - 1)*a(m)*a(n - m)).
%e A143081 {-1},
%e A143081 {1, 1},
%e A143081 {1, 3, 1},
%e A143081 {3, 15, 15, 3},
%e A143081 {15, 105, 175, 105, 15},
%e A143081 {105, 945, 2205, 2205, 945, 105},
%e A143081 {945, 10395, 31185, 43659, 31185, 10395, 945},
%e A143081 {10395, 135135, 495495, 891891, 891891, 495495, 135135, 10395},
%e A143081 {135135, 2027025, 8783775, 19324305, 24845535, 19324305, 8783775, 2027025, 135135},
%e A143081 {2027025, 34459425, 172297125, 447972525, 703956825, 703956825, 447972525, 172297125, 34459425, 2027025}, {34459425, 654729075, 3710131425, 11130394275,
%e A143081 20670732225, 25264228275, 20670732225, 11130394275, 3710131425, 654729075,
%e A143081 34459425}
%t A143081 a[0] = 1; a[n_] := a[n] = (2*n - 1)*a[n - 1]; Table[Table[a[n]^2/((2*n - 1)*a[m]*a[n - m]), {m, 0, n}], {n, 0, 10}]; Flatten[%]
%Y A143081 Cf. A001147.
%K A143081 uned,sign
%O A143081 1,5
%A A143081 _Roger L. Bagula_ and _Gary W. Adamson_, Oct 15 2008