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A050368 Number of ways to factor n into distinct factors with 2 kinds of 2, 3 kinds of 3, ... 21
1, 2, 3, 5, 5, 12, 7, 16, 12, 20, 11, 39, 13, 28, 30, 42, 17, 60, 19, 65, 42, 44, 23, 126, 35, 52, 55, 91, 29, 150, 31, 116, 66, 68, 70, 219, 37, 76, 78, 210, 41, 210, 43, 143, 150, 92, 47, 378, 70, 170, 102, 169, 53, 290, 110, 294, 114, 116, 59, 570, 61, 124, 210 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..1000

FORMULA

Dirichlet g.f.: Product_{n>=2}((1+1/n^s)^n).

PROG

(PARI) seq(n)={my(v=vector(n, k, k==1)); for(k=2, n, my(m=logint(n, k), p=(1 + x + O(x*x^m))^k, w=vector(n)); for(i=0, m, w[k^i]=polcoef(p, i)); v=dirmul(v, w)); v} \\ Andrew Howroyd, Oct 27 2019

CROSSREFS

Cf. A045778, A050367.

Sequence in context: A152076 A133278 A343395 * A156834 A079024 A342421

Adjacent sequences:  A050365 A050366 A050367 * A050369 A050370 A050371

KEYWORD

nonn

AUTHOR

Christian G. Bower, Oct 15 1999

STATUS

approved

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Last modified October 26 02:14 EDT 2021. Contains 348256 sequences. (Running on oeis4.)