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 A064307 #9 Jan 07 2025 20:26:44 %S A064307 1,1,0,1,2,1,1,10,17,2,1,37,181,111,6,1,126,1530,2624,741,18,1,422, %T A064307 11607,43940,34063,4950,57,1,1422,83823,616894,1013799,412698,33337, %U A064307 186,1,4853,593203,7846573,23794925 %N A064307 Triangle of coefficients of certain numerator polynomials N(n,x). %C A064307 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 A064307 Row sums give A001761(n+1). Main diagonal gives A000957(n+1), n >= 0. %F A064307 a(n, m) = [x^m]N(n, x); N(n, x) = (1-x)^(n-1) + Sum_{k=1..n-1} A064308(n-1, k)*k!*x^k*(1-x)^(n-1-k) for n >= 2; N(1, x) = 1 = N(2, x). %e A064307 Triangle begins: %e A064307 1; %e A064307 1, 0; %e A064307 1, 2, 1; N(3,x) = 1+2*x+x^2 = (1+x)^2. %e A064307 1, 10, 17, 2; %e A064307 1, 37, 181, 111, 6; %e A064307 ... %Y A064307 Cf. A000957, A001761, A064094. %K A064307 nonn,tabl %O A064307 1,5 %A A064307 _Wolfdieter Lang_, Sep 13 2001