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 A050369 Number of ordered factorizations of n into 2 kinds of 2, 3 kinds of 3, ... 11
 1, 2, 3, 8, 5, 18, 7, 32, 18, 30, 11, 96, 13, 42, 45, 128, 17, 144, 19, 160, 63, 66, 23, 480, 50, 78, 108, 224, 29, 390, 31, 512, 99, 102, 105, 936, 37, 114, 117, 800, 41, 546, 43, 352, 360, 138, 47, 2304, 98, 400, 153, 416, 53, 1080, 165, 1120, 171, 174, 59, 2640 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Dirichlet inverse of (A000027*A153881). - Mats Granvik, Jan 03 2009 LINKS Vaclav Kotesovec, Table of n, a(n) for n = 1..10000 FORMULA Dirichlet g.f.: 1/(2-zeta(s-1)). a(n) = n*Sum_{d divides n, d1, a(1)=1. - Vladeta Jovovic, Feb 09 2002 Sum_{k=1..n} a(k) ~ -n^(1+r) / ((1+r)*Zeta'(r)), where r = A107311 = 1.728647238998183618135103010297... is the root of the equation Zeta(r) = 2. - Vaclav Kotesovec, Feb 02 2019 G.f. A(x) satisfies: A(x) = x + 2*A(x^2) + 3*A(x^3) + 4*A(x^4) + ... - Ilya Gutkovskiy, May 10 2019 MATHEMATICA a[1]=1; a[n_]:=a[n]=n*Sum[If[d==n, 0, a[d]/d], {d, Divisors[n]}]; Table[a[n], {n, 1, 100}] (* Vaclav Kotesovec, Feb 02 2019 *) CROSSREFS Sequence in context: A004730 A332460 A168014 * A070935 A095164 A075384 Adjacent sequences:  A050366 A050367 A050368 * A050370 A050371 A050372 KEYWORD nonn AUTHOR Christian G. Bower, Oct 15 1999 STATUS approved

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Last modified May 25 11:27 EDT 2020. Contains 334592 sequences. (Running on oeis4.)