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 A210636 #8 Feb 22 2013 14:40:35
%S A210636 1,1,1,3,4,1,7,13,7,1,17,40,32,10,1,41,117,124,60,13,1,99,332,437,286,
%T A210636 97,16,1,239,921,1447,1193,553,143,19,1,577,2512,4584,4556,2682,952,
%U A210636 198,22,1,1393,6761,14048,16336,11666,5282,1510,262,25,1
%N A210636 Riordan array ((1-x)/(1-2*x-x^2), x*(1+x)/(1-2*x-x^2)).
%C A210636 Triangle T(n,k), 0<=k<=n, read by rows, given by (1, 2, -1, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938.
%C A210636 Product of A122542 and A007318 (Pascal's triangle) as lower triangular matrices .
%F A210636 T(n,k) = 2*T(n-1,k) + T(n-1,k-1) + T(n-2,k) + T(n-2,k-1), T(0,0) = T(1,0) = T(1,1) = 1 and T(n,k) = 0 if k<0 or if k>n.
%F A210636 G.f.: (1-x)/(1-2*x-y*x-x^2-y*x^2).
%F A210636 Sum_{k, 0<=k<=n} T(n,k)*x^k = A000007(n), A001333(n), A104934(n), A122958(n), A122690(n), A091928(n) for x = -1, 0, 1, 2, 3, 4 respectively.
%e A210636 Triangle begins :
%e A210636 1
%e A210636 1, 1
%e A210636 3, 4, 1
%e A210636 7, 13, 7, 1
%e A210636 17, 40, 32, 10, 1
%e A210636 41, 117, 124, 60, 13, 1
%e A210636 99, 332, 437, 286, 97, 16, 1
%e A210636 239, 921, 1447, 1193, 553, 143, 19, 1
%e A210636 577, 2512, 4584, 4556, 2682, 952, 198, 22, 1
%e A210636 1393, 6761, 14048, 16336, 11666, 5282, 1510, 262, 25, 1
%Y A210636 Cf. Columns :A001333, A119915, Diagonals : A000012, A016777, Antidiagonal sums : A077995
%K A210636 easy,nonn,tabl
%O A210636 0,4
%A A210636 _Philippe Deléham_, Mar 26 2012