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A323879 Number of divisors d of n such that A276154(d) divides n. 4
0, 1, 0, 1, 0, 2, 0, 1, 0, 1, 0, 3, 0, 1, 0, 1, 0, 2, 0, 1, 0, 1, 0, 4, 0, 1, 0, 1, 0, 3, 0, 1, 0, 1, 0, 3, 0, 1, 0, 1, 0, 2, 0, 2, 0, 1, 0, 4, 0, 1, 0, 1, 0, 2, 0, 1, 0, 1, 0, 5, 0, 1, 0, 1, 0, 2, 0, 1, 0, 2, 0, 5, 0, 1, 0, 1, 0, 2, 0, 1, 0, 1, 0, 3, 0, 1, 0, 2, 0, 4, 0, 1, 0, 1, 0, 4, 0, 1, 0, 1, 0, 2, 0, 1, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..30030

Index entries for sequences related to primorial base

FORMULA

a(n) = Sum_{d|n} [A276154(d)|n], where [ ] is the Iverson bracket.

PROG

(PARI)

A276151(n) = { my(s=1); forprime(p=2, , if(n%p, return(n-s), s *= p)); };

A276152(n) = { my(s=1); forprime(p=2, , if(n%p, return(s*p), s *= p)); };

A276154(n) = if(!n, n, (A276152(n) + A276154(A276151(n))));

A323879(n) = sumdiv(n, d, !(n%A276154(d)));

CROSSREFS

Cf. A002110, A276154.

Cf. also A323878.

Sequence in context: A192174 A262202 A284413 * A129308 A159200 A318721

Adjacent sequences:  A323876 A323877 A323878 * A323880 A323881 A323882

KEYWORD

nonn,base

AUTHOR

Antti Karttunen, Feb 07 2019

STATUS

approved

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Last modified January 28 03:49 EST 2020. Contains 331317 sequences. (Running on oeis4.)