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 A110857 #11 Mar 22 2016 20:21:03 %S A110857 1,0,0,0,1,0,0,1,1,0,0,2,2,2,0,0,5,4,4,5,0,0,14,10,9,10,14,0,0,42,28, %T A110857 23,23,28,42,0,0,132,84,65,60,65,84,132,0,0,429,264,196,171,171,196, %U A110857 264,429,0,0,1430,858,618,518,490,518,618,858,1430,0 %N A110857 Table T(n,k), n>=0, k>=0, product M*M^(T) where M is the lower triangular matrix in A106566 and M^(T) denotes the transpose matrix of M, read by antidiagonals. %e A110857 Matrix M: %e A110857 1, 0, 0, 0, 0, 0, 0, 0, ... %e A110857 0, 1, 0, 0, 0, 0, 0, 0, ... %e A110857 0, 1, 1, 0, 0, 0, 0, 0, ... %e A110857 0, 2, 2, 1, 0, 0, 0, 0, ... %e A110857 0, 5, 5, 3, 1, 0, 0, 0, ... %e A110857 ... %e A110857 Matrix M^(T): %e A110857 1, 0, 0, 0, 0, 0, ... %e A110857 0, 1, 1, 2, 5, 14, ... %e A110857 0, 0, 1, 2, 5, 14, ... %e A110857 0, 0, 0, 1, 3, 9, ... %e A110857 0, 0, 0, 0, 1, 4, ... %e A110857 0, 0, 0, 0, 0, 1, ... %e A110857 ... %e A110857 Table begins: %e A110857 1, 0, 0, 0, 0, 0, 0, ... %e A110857 0, 1, 1, 2, 5, 14, ... %e A110857 0, 1, 2, 4, 10, 28, ... %e A110857 0, 2, 4, 9, 23, 65, ... %e A110857 0, 5, 10, 23, 60, ... %e A110857 0, 14, 28, 65, 171, ... %e A110857 0, 42, 84, 196, ... %Y A110857 Diagonal sums : 1, 0, 1, 2, 6, 18, 57, 186, 622, 2120, ... see A000957. %K A110857 nonn,tabl %O A110857 0,12 %A A110857 _Philippe Deléham_, Sep 17 2005