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Triangle T(n, k) = [x^n] (n + k + x)!/(k + x)! for 0 <= k <= n, read by rows.
2

%I #8 Apr 13 2019 08:09:21

%S 1,1,1,2,5,1,6,26,12,1,24,154,119,22,1,120,1044,1175,355,35,1,720,

%T 8028,12154,5265,835,51,1,5040,69264,133938,77224,17360,1687,70,1,

%U 40320,663696,1580508,1155420,342769,46816,3066,92,1

%N Triangle T(n, k) = [x^n] (n + k + x)!/(k + x)! for 0 <= k <= n, read by rows.

%C Sister triangle of A307419.

%F T(n, k) = Sum_{j=0..n-k} binomial(j+k, k)*|Stirling1(n, j+k)|*(k+1)^j.

%e Triangle starts:

%e [0] 1

%e [1] 1, 1

%e [2] 2, 5, 1

%e [3] 6, 26, 12, 1

%e [4] 24, 154, 119, 22, 1

%e [5] 120, 1044, 1175, 355, 35, 1

%e [6] 720, 8028, 12154, 5265, 835, 51, 1

%e [7] 5040, 69264, 133938, 77224, 17360, 1687, 70, 1

%e [8] 40320, 663696, 1580508, 1155420, 342769, 46816, 3066, 92, 1

%e [9] 362880, 6999840, 19978308, 17893196, 6687009, 1197273, 109494, 5154, 117, 1

%e A000142, A001705, A001712, A001718, A001724, ...

%p T := (n, k) -> add(binomial(j+k, k)*(k+1)^j*abs(Stirling1(n, j+k)), j=0..n-k);

%p seq(seq(T(n,k), k=0..n), n=0..8);

%p # Note that for n > 16 Maple fails (at least in some versions) to compute the

%p # terms properly. Inserting 'simplify' or numerical evaluation might help.

%p A325137Row := proc(n) local ogf, ser; ogf := (n, k) -> (n+k+x)!/(k+x)!;

%p ser := (n, k) -> series(ogf(n,k),x,k+2); seq(coeff(ser(n,k),x,k), k=0..n) end: seq(A325137Row(n), n=0..8);

%Y Row sums: A325138.

%Y Columns are: A000142, A001705, A001712, A001718, A001724.

%Y Cf. A307419.

%K nonn,tabl

%O 0,4

%A _Peter Luschny_, Apr 13 2019