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A328851 Dirichlet g.f.: Product_{k>=2} 1 / (1 - k^(-s))^(k + 1). 2
1, 3, 4, 11, 6, 19, 8, 34, 20, 29, 12, 78, 14, 39, 40, 104, 18, 107, 20, 120, 54, 59, 24, 277, 47, 69, 88, 162, 30, 237, 32, 299, 82, 89, 84, 478, 38, 99, 96, 429, 42, 321, 44, 246, 230, 119, 48, 921, 86, 258, 124, 288, 54, 535, 128, 581, 138, 149, 60, 1091 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Number of ways to factor n into 3 kinds of 2, 4 kinds of 3, ..., k+1 kinds of k.

Dirichlet convolution of A001055 with A050367.

LINKS

Table of n, a(n) for n=1..60.

FORMULA

a(n) = Sum_{d|n} A001055(n/d) * A050367(d).

PROG

(PARI) seq(n)={my(v=vector(n, k, k==1)); for(k=2, n, my(m=logint(n, k), p=1/(1 - x + O(x*x^m))^(1+k), w=vector(n)); for(i=0, m, w[k^i]=polcoef(p, i)); v=dirmul(v, w)); v} \\ Andrew Howroyd, Oct 28 2019

CROSSREFS

Cf. A001055, A050367, A328853.

Sequence in context: A133760 A335887 A335888 * A197953 A198299 A175317

Adjacent sequences:  A328848 A328849 A328850 * A328852 A328853 A328854

KEYWORD

nonn

AUTHOR

Ilya Gutkovskiy, Oct 28 2019

STATUS

approved

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Last modified September 18 01:39 EDT 2021. Contains 347504 sequences. (Running on oeis4.)