[go: up one dir, main page]

login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Triangle of coefficients of certain numerator polynomials N(n,x).
1

%I #6 Jul 25 2022 08:02:58

%S 1,1,0,1,2,1,1,10,17,2,1,37,181,111,6,1,126,1530,2624,741,18,1,422,

%T 11607,43940,34063,4950,57,1,1422,83823,616894,1013799,412698,33337,

%U 186,1,4853,593203,7846573,23794925

%N Triangle of coefficients of certain numerator polynomials N(n,x).

%C The g.f. for the sequence in the subdiagonal d>=1 (main diagonal: d=0) of triangle A064094 is N(d,x)/(1-x)^d.

%C Row sums give A001761(n+1). Main diagonal gives A000957(n+1), n >= 0.

%F a(n, m) = [x^m]N(n, x); N(n, x)= (1-x)^(n-1) + sum(A064308(n-1, k)*k!*x^k*(1-x)^(n-1-k), k=1..n-1)) for n >= 2; N(1, x)=1=N(2, x).

%e Triangle begins:

%e 1;

%e 1, 0;

%e 1, 2, 1; N(3,x) = 1+2*x+x^2 = (1+x)^2.

%e 1, 10, 17, 2;

%e 1, 37, 181, 111, 6;

%e ...

%Y Cf. A000957, A001761, A064094.

%K nonn,tabl

%O 1,5

%A _Wolfdieter Lang_, Sep 13 2001