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A327861 Number of divisors d of n for which A003415(d)*d is equal to n, where A003415(x) gives the arithmetic derivative of x. 2
0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4153248

COMMENTS

Number of times n occurs in A190116.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

EXAMPLE

a(4153248)=2 as out of 192 divisors of 4153248, only 1368 and 2277 are such that 1368 * A003415(1368) = 2277 * A003415(2277) = 4153248.

PROG

(PARI)

A003415(n) = {my(fac); if(n<1, 0, fac=factor(n); sum(i=1, matsize(fac)[1], n*fac[i, 2]/fac[i, 1]))}; \\ From A003415

A327861(n) = sumdiv(n, d, (d*A003415(d) == n));

CROSSREFS

Cf. A003415, A190116.

Cf. also A327153, A327166, A327169.

Sequence in context: A010051 A252233 A283991 * A131929 A100821 A139689

Adjacent sequences:  A327858 A327859 A327860 * A327862 A327863 A327864

KEYWORD

nonn

AUTHOR

Antti Karttunen, Sep 28 2019

STATUS

approved

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Last modified November 15 14:06 EST 2019. Contains 329149 sequences. (Running on oeis4.)