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A111221 d_11(n), tau_11(n), number of ordered factorizations of n as n = rstuvwxyzab (11-factorizations). 5
1, 11, 11, 66, 11, 121, 11, 286, 66, 121, 11, 726, 11, 121, 121, 1001, 11, 726, 11, 726, 121, 121, 11, 3146, 66, 121, 286, 726, 11, 1331, 11, 3003, 121, 121, 121, 4356, 11, 121, 121, 3146, 11, 1331, 11, 726, 726, 121, 11, 11011, 66, 726, 121, 726, 11, 3146, 121 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Seiichi Manyama, Table of n, a(n) for n = 1..10000 (terms 1..1000 from Enrique PĂ©rez Herrero)

FORMULA

G.f.: Sum_{k>=1} tau_10(k)*x^k/(1 - x^k). - Ilya Gutkovskiy, Oct 30 2018

MATHEMATICA

tau[n_, 1] = 1; tau[n_, k_] := tau[n, k] = Plus @@ (tau[ #, k - 1] & /@ Divisors[n]); Table[ tau[n, 11], {n, 55}] (* Robert G. Wilson v, Nov 02 2005 *)

PROG

(PARI) for(n=1, 100, print1(sumdiv(n, i, sumdiv(i, j, sumdiv(j, k, sumdiv(k, l, sumdiv(l, m, sumdiv(m, o, sumdiv(o, p, sumdiv(p, q, sumdiv(q, x, numdiv(x)))))))))), ", "))

(PARI) a(n, f=factor(n))=f=f[, 2]; prod(i=1, #f, binomial(f[i]+10, 10)) \\ Charles R Greathouse IV, Oct 28 2017

CROSSREFS

Cf. tau_1(n): A000012

Cf. tau_2(n)...tau_6(n): A000005, A007425, A007426, A061200, A034695.

Cf. tau_7(n)...tau_10(n): A111217, A111218, A111219, A111220.

Cf. tau_12(n): A111306.

Column k=11 of A077592.

Sequence in context: A228768 A003876 A014461 * A241870 A243127 A088761

Adjacent sequences:  A111218 A111219 A111220 * A111222 A111223 A111224

KEYWORD

mult,nonn

AUTHOR

Gerald McGarvey, Oct 25 2005

STATUS

approved

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Last modified March 19 00:15 EDT 2019. Contains 321306 sequences. (Running on oeis4.)