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 A355607 #21 Jul 11 2022 03:36:13 %S A355607 1,1,1,1,0,0,1,0,2,0,1,0,0,-3,0,1,0,0,6,20,0,1,0,0,0,-12,-90,0,1,0,0, %T A355607 0,24,40,594,0,1,0,0,0,0,-60,180,-4200,0,1,0,0,0,0,120,240,-1512, %U A355607 34544,0,1,0,0,0,0,0,-360,-1260,11760,-316008,0,1,0,0,0,0,0,720,1680,28224,-38880,3207240,0 %N A355607 Square array T(n,k), n>=0, k>=0, read by antidiagonals, where column k is the expansion of e.g.f. (1 + x)^(x^k). %H A355607 Seiichi Manyama, <a href="/A355607/b355607.txt">Antidiagonals n = 0..139, flattened</a> %F A355607 T(0,k) = 1 and T(n,k) = -(n-1)! * Sum_{j=k+1..n} (-1)^(j-k) * j/(j-k) * T(n-j,k)/(n-j)! for n > 0. %F A355607 T(n,k) = n! * Sum_{j=0..floor(n/(k+1))} Stirling1(n-k*j,j)/(n-k*j)!. %e A355607 Square array begins: %e A355607 1, 1, 1, 1, 1, 1, 1, ... %e A355607 1, 0, 0, 0, 0, 0, 0, ... %e A355607 0, 2, 0, 0, 0, 0, 0, ... %e A355607 0, -3, 6, 0, 0, 0, 0, ... %e A355607 0, 20, -12, 24, 0, 0, 0, ... %e A355607 0, -90, 40, -60, 120, 0, 0, ... %e A355607 0, 594, 180, 240, -360, 720, 0, ... %o A355607 (PARI) T(n, k) = n!*sum(j=0, n\(k+1), stirling(n-k*j, j, 1)/(n-k*j)!); %Y A355607 Columns k=1..4 give A007113, A007121, (-1)^n * A353229(n), A354625. %Y A355607 Cf. A292892, A355609, A355619. %K A355607 sign,tabl,look %O A355607 0,9 %A A355607 _Seiichi Manyama_, Jul 09 2022