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 A333142 #11 Mar 09 2020 13:10:37 %S A333142 1,1,1,1,2,1,1,7,5,1,1,50,42,12,1,1,751,680,222,27,1,1,23282,21831, %T A333142 7562,1059,58,1,1,1466767,1398635,498237,74279,4713,121,1,1,186279410, %U A333142 179093412,64674734,9931670,672830,20080,248,1 %N A333142 Triangle read by rows: T(n, k) = qStirling1(n, k, q) for q = 2, with 0 <= k <= n. %F A333142 qStirling1(n, k, q) = qStirling1(n-1, k-1, q) + qBrackets(n-1, q)*qStirling1(n-1, k, q) with boundary values 0^k if n = 0 and n^0 if k = 0. %F A333142 Note that also a second definition is used in the literature. The two versions differ by a factor of q^(n-k). %e A333142 Triangle starts: %e A333142 [0] 1 %e A333142 [1] 1, 1 %e A333142 [2] 1, 2, 1 %e A333142 [3] 1, 7, 5, 1 %e A333142 [4] 1, 50, 42, 12, 1 %e A333142 [5] 1, 751, 680, 222, 27, 1 %e A333142 [6] 1, 23282, 21831, 7562, 1059, 58, 1 %e A333142 [7] 1, 1466767, 1398635, 498237, 74279, 4713, 121, 1 %e A333142 [8] 1, 186279410, 179093412, 64674734, 9931670, 672830, 20080, 248, 1 %p A333142 qStirling1 := proc(n, k, q) option remember; with(QDifferenceEquations): %p A333142 if n = 0 then return 0^k fi; if k = 0 then return n^0 fi; %p A333142 qStirling1(n-1, k-1, p) + QBrackets(n-1, p)*qStirling1(n-1, k, p); %p A333142 subs(p = q, expand(%)) end: %p A333142 seq(seq(qStirling1(n, k, 2), k=0..n), n=0..9); %Y A333142 T(n,n-1) = A000325(n). %Y A333142 Cf. A333143. %K A333142 nonn,tabl %O A333142 0,5 %A A333142 _Peter Luschny_, Mar 09 2020