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A111217
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d_7(n), tau_7(n), number of ordered factorizations of n as n = rstuvwx (7-factorizations).
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4
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1, 7, 7, 28, 7, 49, 7, 84, 28, 49, 7, 196, 7, 49, 49, 210, 7, 196, 7, 196, 49, 49, 7, 588, 28, 49, 84, 196, 7, 343, 7, 462, 49, 49, 49, 784, 7, 49, 49, 588, 7, 343, 7, 196, 196, 49, 7, 1470, 28, 196, 49, 196, 7, 588, 49, 588, 49, 49, 7, 1372, 7, 49, 196, 924, 49, 343, 7, 196
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OFFSET
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1,2
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LINKS
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Enrique Pérez Herrero, Table of n, a(n) for n = 1..1000
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FORMULA
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Dirichlet convolution of A000012 with A034695, or of A000005 with A061200, or of A007425 with A007426. Dirichlet g.f. zeta^7(s). - R. J. Mathar, Apr 01 2011
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MATHEMATICA
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tau[n_, 1] = 1; tau[n_, k_] := tau[n, k] = Plus @@ (tau[ #, k - 1] & /@ Divisors[n]); Table[ tau[n, 7], {n, 68}] (from Robert G. Wilson v, Nov 02 2005)
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PROG
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(PARI) for(n=1, 100, print1(sumdiv(n, i, sumdiv(i, j, sumdiv(j, k, sumdiv(k, l, sumdiv(l, x, numdiv(x)))))), ", "))
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CROSSREFS
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Cf. tau_k(n) for k>=2: A000005, A007425, A007426, A061200, A034695, A111218 - A111221, A111306.
Sequence in context: A059772 A114369 A027844 * A198341 A186142 A188274
Adjacent sequences: A111214 A111215 A111216 * A111218 A111219 A111220
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KEYWORD
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mult,nonn
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AUTHOR
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Gerald McGarvey, Oct 25 2005
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STATUS
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approved
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