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A322584 Number of divisors of n that area product of primorial numbers (terms of A025487). 4
1, 2, 1, 3, 1, 3, 1, 4, 1, 2, 1, 5, 1, 2, 1, 5, 1, 3, 1, 3, 1, 2, 1, 7, 1, 2, 1, 3, 1, 4, 1, 6, 1, 2, 1, 6, 1, 2, 1, 4, 1, 3, 1, 3, 1, 2, 1, 9, 1, 2, 1, 3, 1, 3, 1, 4, 1, 2, 1, 7, 1, 2, 1, 7, 1, 3, 1, 3, 1, 2, 1, 9, 1, 2, 1, 3, 1, 3, 1, 5, 1, 2, 1, 5, 1, 2, 1, 4, 1, 4, 1, 3, 1, 2, 1, 11, 1, 2, 1, 3, 1, 3, 1, 4, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n) is the number of terms of A025487 that divide n.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..20000

Antti Karttunen, Data supplement: n, a(n) computed for n = 1..100000

FORMULA

a(n) = Sum_{d|} A322585(d).

PROG

(PARI)

A322585(n) = { my(f = factor(n)); for(i=1, #f~, if((primepi(f[i, 1])!=i)||((i>1)&&(f[i-1, 2]<f[i, 2])), return(0))); (1); };

A322584(n) = sumdiv(n, d, A322585(d));

CROSSREFS

Inverse Möbius transform of A322585.

Cf. A025487.

Cf. also A181801.

Sequence in context: A073407 A049994 A135732 * A326154 A306248 A084360

Adjacent sequences:  A322581 A322582 A322583 * A322585 A322586 A322587

KEYWORD

nonn

AUTHOR

Antti Karttunen, Dec 20 2018

STATUS

approved

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Last modified September 17 22:53 EDT 2019. Contains 327147 sequences. (Running on oeis4.)