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 A368759 #13 Jan 05 2024 07:57:18 %S A368759 2,1,3,1,2,7,1,2,6,22,1,2,8,21,89,1,2,12,33,88,446,1,2,20,63,148,445, %T A368759 2677,1,2,36,141,316,765,2676,18740,1,2,68,351,820,1705,4626,18739, %U A368759 149921,1,2,132,933,2428,4725,10446,32431,149920,1349290,1,2,260,2583,7828,15265,29646,73465,259512,1349289,13492901 %N A368759 Square array T(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where T(n,k) = n! * (1 + Sum_{j=0..n} j^k/j!). %H A368759 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/BellPolynomial.html">Bell Polynomial</a>. %H A368759 Wikipedia, <a href="https://en.wikipedia.org/wiki/Touchard_polynomials">Touchard polynomials</a>. %F A368759 T(0,k) = 1 + 0^k and T(n,k) = n^k + n * T(n-1,k) for n>0. %F A368759 T(n,k) = n! + A337085(n,k). %F A368759 E.g.f. of column k: (1+ B_k(x) * exp(x)) / (1-x), where B_n(x) = Bell polynomials. %e A368759 Square array begins: %e A368759 2, 1, 1, 1, 1, 1, 1, ... %e A368759 3, 2, 2, 2, 2, 2, 2, ... %e A368759 7, 6, 8, 12, 20, 36, 68, ... %e A368759 22, 21, 33, 63, 141, 351, 933, ... %e A368759 89, 88, 148, 316, 820, 2428, 7828, ... %e A368759 446, 445, 765, 1705, 4725, 15265, 54765, ... %e A368759 2677, 2676, 4626, 10446, 29646, 99366, 375246, ... %o A368759 (PARI) T(n, k) = n!*(1+sum(j=0, n, j^k/j!)); %Y A368759 Columns k=0..3 give A038159, A033540(n+1), A053817, A368760. %Y A368759 Cf. A337085. %K A368759 nonn,tabl %O A368759 0,1 %A A368759 _Seiichi Manyama_, Jan 04 2024