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A064307
Triangle of coefficients of certain numerator polynomials N(n,x).
1
1, 1, 0, 1, 2, 1, 1, 10, 17, 2, 1, 37, 181, 111, 6, 1, 126, 1530, 2624, 741, 18, 1, 422, 11607, 43940, 34063, 4950, 57, 1, 1422, 83823, 616894, 1013799, 412698, 33337, 186, 1, 4853, 593203, 7846573, 23794925
OFFSET
1,5
COMMENTS
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.
Row sums give A001761(n+1). Main diagonal gives A000957(n+1), n >= 0.
FORMULA
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).
EXAMPLE
Triangle begins:
1;
1, 0;
1, 2, 1; N(3,x) = 1+2*x+x^2 = (1+x)^2.
1, 10, 17, 2;
1, 37, 181, 111, 6;
...
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Wolfdieter Lang, Sep 13 2001
STATUS
approved