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A171453 a(n) = sum_i p_i^(e_i-1) where n = product_i p_i^e_i is the prime number decomposition of n. 1
0, 1, 1, 2, 1, 2, 1, 4, 3, 2, 1, 3, 1, 2, 2, 8, 1, 4, 1, 3, 2, 2, 1, 5, 5, 2, 9, 3, 1, 3, 1, 16, 2, 2, 2, 5, 1, 2, 2, 5, 1, 3, 1, 3, 4, 2, 1, 9, 7, 6, 2, 3, 1, 10, 2, 5, 2, 2, 1, 4, 1, 2, 4, 32, 2, 3, 1, 3, 2, 3, 1, 7, 1, 2, 6, 3, 2, 3, 1, 9, 27, 2, 1, 4, 2, 2, 2, 5, 1, 5, 2, 3, 2, 2, 2, 17, 1, 8, 4, 7 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A008475(n) - A067240(n).

MAPLE

A171453 := proc(n) add( op(1, f)^(op(2, f)-1), f =ifactors(n)[2]) ; end proc:

seq(A171453(n), n=1..100) ;

PROG

(PARI) A171453(n) = { my(f=factor(n)); vecsum(vector(#f~, i, f[i, 1]^(f[i, 2]-1))); }; \\ Antti Karttunen, Sep 24 2017

CROSSREFS

Cf. A008475, A067240.

Sequence in context: A135545 A123317 A231557 * A285707 A164879 A200219

Adjacent sequences:  A171450 A171451 A171452 * A171454 A171455 A171456

KEYWORD

easy,nonn

AUTHOR

R. J. Mathar, Dec 09 2009

STATUS

approved

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Last modified October 14 01:36 EDT 2019. Contains 327994 sequences. (Running on oeis4.)