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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.

A196847 Coefficient table of numerator polynomials of the ordinary generating function for the alternating power sums for the numbers 1,2,...,2*n.

Original entry on oeis.org

1, 1, -5, 7, 1, -14, 73, -168, 148, 1, -27, 298, -1719, 5473, -9162, 6396, 1, -44, 830, -8756, 56453, -227744, 562060, -778800, 468576, 1, -65, 1865, -31070, 332463, -2385305, 11612795, -37875240, 79269676, -96420480, 52148160, 1, -90, 3647, -87900, 140202
Offset: 1

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Author

Wolfdieter Lang, Oct 27 2011

Keywords

Comments

The row length sequence of this array is A005408(n-1), n >= 1: 1,3,5,7,...
This is the array for the numerator polynomials of the o.g.f. of alternating power sums of the first 2*n positive integers.
The corresponding array for the first 2*n+1 positive integers is found in A196848.
The obvious e.g.f. of a(k,2*n) := Sum_{j=1..2*n} (-1)^j * j^k is ge(n,x) := Sum_{k>=0} a(k,2*n)*(x^k)/k! = Sum_{j=1..2*n} (-1)^j * exp(j*x) = exp(x)*(exp(2*n*x) - 1)/(exp(x) + 1).
Via Laplace transformation (see the link under A196837, addendum) one finds the corresponding o.g.f.: Ge(n,x) = n*x*Pe(n,x)/Product_{j=1..2*n} (1 - j*x) with the numerator polynomial Pe(n,x) = Sum_{m=0..2*(n-1)} a(n,m)*x^m.

Examples

			n\m 0   1   2     3     4       5      6       7      8
1:  1
2:  1  -5   7
3:  1 -14  73  -168   148
4:  1 -27 298 -1719  5473   -9162   6396
5:  1 -44 830 -8756 56453 -227744 562060 -778800 468576
...
The o.g.f. for the sequence a(k,4) := -(1^k - 2^k + 3^k -4^k) = 2*A053154(k), k>=0, (n=2) is Ge(2,x) = 2*x*(1-5*x+7*x^2)/Product_{j=1..4} (1 - j*x).
a(3,2) = (S_{1,2}(4,2) + S_{3,4}(4,2) + S_{5,6}(4,2))/3 = (A196845(4,2) + A196846(4,2) + |s(5,3)|)/3 = (119+65+35)/3 = 73. Here S_{5,6}(4,2) = a_2(1,2,3,4) = |s(5,3)|, with the Stirling numbers of the first kind s(n,m) = A048994(n,m) was used.
		

Crossrefs

Formula

a(n,m) = [x^m](Ge(n,x)*Product_{j=1..2*n} (1 - j*x/(n*x))), with the o.g.f. Ge(n,x) of the sequence a(k,2*n) := Sum_{j=1..2*n} (-1)^j * j^k. See a comment above.
a(n,m) = (1/n)*(-1)^m*Sum_{i=1..n} S_{2*i-1,2*i}(2*(n-1),m), n >= 1, with the (i,j)-family of number triangles S_{i,j}(n,k) defined in a comment to A196845.