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 A164976 #26 Oct 15 2023 14:26:35 %S A164976 1,1,2,0,5,4,-1,4,16,8,-1,-3,25,44,16,0,-10,7,102,112,32,1,-8,-41,97, %T A164976 344,272,64,1,4,-74,-80,528,1040,640,128,0,15,-33,-366,121,2168,2928, %U A164976 1472,256,-1,12,75,-426,-1219,1898,7664,7840,3328,512 %N A164976 Triangle read by rows, expansion of 1/(1-2*y*x-x+x^2-y*x^2). %C A164976 Leftmost column is A010892. %C A164976 Rows sum up to A000244 and diagonals to A000073. %C A164976 A164975 has a similar g.f.: x/(1-2*y*x-x-x^2+y*x^2).. - _Georg Fischer_, Oct 15 2023 %H A164976 Georg Fischer, <a href="/A164976/b164976.txt">Table of n, a(n) for n = 1..5050</a> %e A164976 Triangle begins: %e A164976 1; %e A164976 1, 2; %e A164976 0, 5, 4; %e A164976 -1, 4, 16, 8; %e A164976 -1, -3, 25, 44, 16; %e A164976 0, -10, 7, 102, 112, 32; %e A164976 1, -8, -41, 97, 344, 272, 64; %e A164976 ... %p A164976 s := 1/(1-2*y*x-x+x^2-y*x^2): t := series(s, x, 12): %p A164976 seq(print(seq(coeff(coeff(t, x, n), y, m), m=0..n)), n=0..11); # _Georg Fischer_, Oct 15 2023 %Y A164976 Cf. A164975, A000244, A000045, A164965, A000073. %Y A164976 Cf. A010892 (1st column), A000079 (right diagonal). %K A164976 tabl,sign %O A164976 0,3 %A A164976 _Mark Dols_, Sep 03 2009 %E A164976 Missing commas inserted in what used to be the term "1-8-41" (now "1,-8,-41") by Geoff Bailey (geoff(AT)maths.usyd.edu.au), Nov 30 2009 %E A164976 Definition changed by _Georg Fischer_, Oct 15 2023