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 A055374 #19 Jan 21 2020 10:25:34 %S A055374 1,1,1,4,8,4,16,48,48,16,64,256,384,256,64,256,1280,2560,2560,1280, %T A055374 256,1024,6144,15360,20480,15360,6144,1024,4096,28672,86016,143360, %U A055374 143360,86016,28672,4096,16384,131072,458752,917504,1146880,917504 %N A055374 Invert transform applied three times to Pascal's triangle A007318. %C A055374 Triangle T(n,k), 0 <= k <= n, read by rows, given by [1, 3, 0, 0, 0, 0, 0, 0, 0, ...] DELTA [1, 3, 0, 0, 0, 0, 0, 0, 0, ...] where DELTA is the operator defined in A084938. - _Philippe Deléham_, Aug 10 2005 %H A055374 N. J. A. Sloane, <a href="/transforms.txt">Transforms</a> %H A055374 <a href="/index/Pas#Pascal">Index entries for triangles and arrays related to Pascal's triangle</a> %F A055374 a(n,k) = 4^(n-1)*C(n, k), for n>0. %F A055374 G.f.: (-1+3*x+3*x*y)/(-1+4*x+4*x*y). - _R. J. Mathar_, Aug 12 2015 %e A055374 1; %e A055374 1, 1; %e A055374 4, 8, 4; %e A055374 16, 48, 48, 16; %e A055374 64, 256, 384, 256, 64; ... %Y A055374 Cf. A000302, A007318, A055372, A055373. %K A055374 nonn,tabl,easy %O A055374 0,4 %A A055374 _Christian G. Bower_, May 16 2000