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 A216230 #9 Mar 15 2013 12:41:06
%S A216230 1,1,0,0,1,0,0,1,0,0,0,0,1,0,0,0,0,1,0,0,0,0,0,0,1,0,0,0,0,0,0,1,0,0,
%T A216230 0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,
%U A216230 0,0
%N A216230 Square array T, read by antidiagonals: T(n,k) = 0 if n-k>=1 or if k-n>=2, T(0,0) = T(0,1) = 1, T(n,k) = T(n-1,k) + T(n,k-1).
%F A216230 T(n,n) = T(n,n+1) = 1.
%F A216230 Sum_{k, 0<=k<=n} T(n-k, k) = 1.
%e A216230 Square array begins:
%e A216230 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ...
%e A216230 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, ...
%e A216230 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, ...
%e A216230 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, ...
%e A216230 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, ...
%e A216230 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, ...
%e A216230 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, ...
%e A216230 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, ...
%e A216230 ...
%Y A216230 Cf. A000012, A068914
%Y A216230 Cf. Similar sequences: A216201, A216210, A216216, A216218, A216219, A216220, A216226, A216228, A216229
%K A216230 nonn,tabl
%O A216230 0,1
%A A216230 _Philippe Deléham_, Mar 14 2013