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A328851 Dirichlet g.f.: Product_{k>=2} 1 / (1 - k^(-s))^(k + 1). 3
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
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
Sequence in context: A133760 A335887 A335888 * A197953 A198299 A360948
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Oct 28 2019
STATUS
approved

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Last modified April 19 10:31 EDT 2024. Contains 371791 sequences. (Running on oeis4.)