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A023006 Number of partitions of n into parts of 7 kinds. 5
1, 7, 35, 140, 490, 1547, 4522, 12405, 32305, 80465, 192899, 447146, 1006145, 2204475, 4715510, 9869132, 20247710, 40786690, 80782800, 157510780, 302666903, 573720808, 1073720305, 1985506775, 3630307835, 6567206471, 11760658378, 20860415590, 36665885170, 63891010155, 110415782785, 189320804673, 322174588225 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
a(n) is Euler transform of A010727. - Alois P. Heinz, Oct 17 2008
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..1000 (first 201 terms from Vincenzo Librandi)
Roland Bacher, P. De La Harpe, Conjugacy growth series of some infinitely generated groups. 2016, hal-01285685v2.
P. Nataf, M. Lajkó, A. Wietek, K. Penc, F. Mila, A. M. Läuchli, Chiral spin liquids in triangular lattice SU (N) fermionic Mott insulators with artificial gauge fields, arXiv preprint arXiv:1601.00958 [cond-mat.quant-gas], 2016.
N. J. A. Sloane, Transforms
FORMULA
G.f.: Product_{m>=1} 1/(1-x^m)^7.
a(n) ~ 49 * exp(Pi * sqrt(14*n/3)) / (576 * sqrt(2) * n^(5/2)). - Vaclav Kotesovec, Feb 28 2015
a(0) = 1, a(n) = (7/n)*Sum_{k=1..n} A000203(k)*a(n-k) for n > 0. - Seiichi Manyama, Mar 26 2017
G.f.: exp(7*Sum_{k>=1} x^k/(k*(1 - x^k))). - Ilya Gutkovskiy, Feb 06 2018
MAPLE
with(numtheory): a:= proc(n) option remember; `if`(n=0, 1, add(add(d*7, d=divisors(j)) *a(n-j), j=1..n)/n) end: seq(a(n), n=0..40); # Alois P. Heinz, Oct 17 2008
MATHEMATICA
nmax=50; CoefficientList[Series[Product[1/(1-x^k)^7, {k, 1, nmax}], {x, 0, nmax}], x] (* Vaclav Kotesovec, Feb 28 2015 *)
PROG
(PARI) Vec(1/eta('x+O('x^66))^7) /* Joerg Arndt, Jul 30 2011 */
CROSSREFS
Cf. 7th column of A144064. - Alois P. Heinz, Oct 17 2008
Sequence in context: A320050 A160460 A160539 * A001875 A169794 A240418
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified March 19 07:19 EDT 2024. Contains 370954 sequences. (Running on oeis4.)