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 A119326 #21 Mar 30 2023 16:08:30 %S A119326 1,1,1,1,1,1,1,1,1,1,1,1,2,1,1,1,1,4,4,1,1,1,1,7,10,7,1,1,1,1,11,19, %T A119326 19,11,1,1,1,1,16,31,38,31,16,1,1,1,1,22,46,66,66,46,22,1,1,1,1,29,64, %U A119326 106,126,106,64,29,1,1,1,1,37,85,162,226,226,162,85,37,1,1 %N A119326 Number triangle T(n,k) = Sum_{j=0..n-k} C(k,2j)*C(n-k,2j). %C A119326 Third column is essentially A000124. Fourth column is essentially A005448. Fifth column is A119327. Product of Pascal's triangle A007318 and A119328. Row sums are A038504. T(n,k) = T(n,n-k). %D A119326 Lukas Spiegelhofer and Jeffrey Shallit, Continuants, Run Lengths, and Barry's Modified Pascal Triangle, Volume 26(1) 2019, of The Electronic Journal of Combinatorics, #P1.31. %H A119326 Seiichi Manyama, <a href="/A119326/b119326.txt">Rows n = 0..139, flattened</a> %H A119326 Jeffrey Shallit, Lukas Spiegelhofer, <a href="https://arxiv.org/abs/1710.06203">Continuants, run lengths, and Barry's modified Pascal triangle</a>, arXiv:1710.06203 [math.CO], 2017. %F A119326 Column k has g.f.: (x^k/(1-x))* Sum{j=0..k} C(k,2j)*(x/(1-x))^(2j). %F A119326 T(2n,n) = A119358(n). - _Alois P. Heinz_, Aug 31 2018 %e A119326 Triangle begins: %e A119326 1; %e A119326 1, 1; %e A119326 1, 1, 1; %e A119326 1, 1, 1, 1; %e A119326 1, 1, 2, 1, 1; %e A119326 1, 1, 4, 4, 1, 1; %e A119326 1, 1, 7, 10, 7, 1, 1; %e A119326 1, 1, 11, 19, 19, 11, 1, 1; %e A119326 ... %Y A119326 Cf. A119358. %K A119326 easy,nonn,tabl %O A119326 0,13 %A A119326 _Paul Barry_, May 14 2006