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 A108063 #2 Mar 30 2012 17:28:32 %S A108063 0,0,0,1,0,1,1,0,0,1,1,-1,0,-1,1,2,-1,0,0,-1,2,4,-1,1,0,1,-1,4,6,-2,1, %T A108063 0,0,1,-2,6,9,-4,1,-1,0,-1,1,-4,9,15,-6,2,-1,0,0,-1,2,-6,15,25,-9,4, %U A108063 -1,1,0,1,-1,4,-9,25,40,-15,6,-2,1,0,0,1,-2,6,-15,40,64,-25,9,-4,1,-1,0,-1,1,-4,9,-25,64,104,-40,15,-6,2,-1,0,0,-1,2,-6 %N A108063 Triangle, read by rows, where T(n,k) = A006498(n+1) - A106408(n,k). A006498 are the central numbers of A106408. %C A108063 Each entry is +- an entry in A006498. Each column and each diagonal contains either A006498 or -A006498. For n>2, each row contains an alternating-signed version of a subsequence of A006498, both in forward and reverse order. For n>2 each column contains an alternating-signed version of a contiguous subsequence of A006498 in reverse order. %Y A108063 Cf. A006498, A106408. %K A108063 sign,tabl %O A108063 1,16 %A A108063 _Gerald McGarvey_, Jun 02 2005