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 A184879 #23 Sep 08 2022 08:45:55
%S A184879 1,1,1,1,-2,1,1,-1,-1,1,1,4,6,4,1,1,13,2,2,13,1,1,26,-17,-20,-17,26,1,
%T A184879 1,43,-39,-5,-5,-39,43,1,1,64,-36,64,70,64,-36,64,1,1,89,36,116,14,14,
%U A184879 116,36,89,1,1,118,237,8,-238,-252,-238,8,237,118,1,1,151,643,-395,-358
%N A184879 Triangular array T read by rows: T(n, k) = Sum_{i=0..2*n-2*k} binomial(2*n-2*k, i)*binomial(2*k, i)*(-1)^i, 0 <= k <= n.
%C A184879 Row sums are in A108474, antidiagonal sums are in A184880.
%C A184879 T(2*n, n) is (-1)^n*A000984, T(2*n ,n)-T(2*n, n+1) is A184881.
%e A184879 Triangle begins
%e A184879 1;
%e A184879 1, 1;
%e A184879 1, -2, 1;
%e A184879 1, -1, -1, 1;
%e A184879 1, 4, 6, 4, 1;
%e A184879 1, 13, 2, 2, 13, 1;
%e A184879 1, 26, -17, -20, -17, 26, 1;
%e A184879 1, 43, -39, -5, -5, -39, 43, 1;
%e A184879 1, 64, -36, 64, 70, 64, -36, 64, 1;
%e A184879 1, 89, 36, 116, 14, 14, 116, 36, 89, 1;
%e A184879 1, 118, 237, 8, -238, -252, -238, 8, 237, 118, 1;
%o A184879 (Magma) &cat[ [ &+[ Binomial(2*n-2*k, i)*Binomial(2*k, i)*(-1)^i: i in [0..(2*n-2*k)] ]: k in [0..n] ]: n in [0..11] ]; // _Klaus Brockhaus_, Feb 10 2011
%Y A184879 Cf. A007318, A000984, A108474, A184880, A184881.
%K A184879 sign,tabl
%O A184879 0,5
%A A184879 _Paul Barry_, Jan 24 2011
%E A184879 Edited by _Klaus Brockhaus_, Feb 10 2011