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 A294046 #21 Nov 03 2017 11:53:25 %S A294046 1,1,0,1,1,0,1,2,3,0,1,3,10,13,0,1,4,21,68,73,0,1,5,36,195,580,501,0, %T A294046 1,6,55,424,2241,5912,4051,0,1,7,78,785,6136,30483,69784,37633,0,1,8, %U A294046 105,1308,13705,104544,476469,933200,394353,0,1,9,136,2023,26748 %N A294046 Square array A(n,k), n >= 0, k >= 0, read by antidiagonals, where column k is the expansion of e.g.f.: exp(1/(1-x)^k - 1). %H A294046 Seiichi Manyama, <a href="/A294046/b294046.txt">Antidiagonals n = 0..139, flattened</a> %F A294046 A(0,k) = 1 and A(n,k) = k * (n-1)! * Sum_{j=1..n} binomial(j+k-1,k)*A(n-j,k)/(n-j)! for n > 0. %e A294046 Square array A(n,k) begins: %e A294046 1, 1, 1, 1, 1, ... %e A294046 0, 1, 2, 3, 4, ... %e A294046 0, 3, 10, 21, 36, ... %e A294046 0, 13, 68, 195, 424, ... %e A294046 0, 73, 580, 2241, 6136, ... %e A294046 0, 501, 5912, 30483, 104544, ... %t A294046 A[0, _] = 1; A[n_, k_] := k*(n-1)!*Sum[Binomial[j+k-1, k]*A[n-j, k]/(n-j)!, {j, 1, n}]; %t A294046 Table[A[n-k, k], {n, 0, 10}, {k, n, 0, -1}] // Flatten (* _Jean-François Alcover_, Nov 03 2017 *) %Y A294046 Columns k=0..5 give A000007, A000262, A136658, A202826, A294050, A294051. %Y A294046 Rows n=0..2 give A000012, A001477, A014105. %Y A294046 Main diagonal gives A294047. %Y A294046 Cf. A291709. %K A294046 nonn,tabl %O A294046 0,8 %A A294046 _Seiichi Manyama_, Oct 22 2017