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A324848 Number of prime indices of n (counted with multiplicity) that divide n. 16
0, 1, 0, 2, 0, 2, 0, 3, 0, 1, 0, 3, 0, 1, 1, 4, 0, 3, 0, 2, 0, 1, 0, 4, 0, 1, 0, 3, 0, 3, 0, 5, 0, 1, 0, 4, 0, 1, 0, 3, 0, 2, 0, 2, 1, 1, 0, 5, 0, 1, 0, 2, 0, 4, 1, 4, 0, 1, 0, 4, 0, 1, 0, 6, 0, 2, 0, 2, 0, 1, 0, 5, 0, 1, 2, 2, 0, 3, 0, 4, 0, 1, 0, 4, 0, 1, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.

LINKS

Table of n, a(n) for n=1..87.

EXAMPLE

The prime indices of 6776 are {1,1,1,4,5,5}, four of which {1,1,1,4} divide 6776, so a(6776) = 4.

MATHEMATICA

Table[Total[Cases[If[n==1, {}, FactorInteger[n]], {p_, k_}:>k/; Divisible[n, PrimePi[p]]]], {n, 100}]

CROSSREFS

The version for distinct prime indices is A324852.

Positions of zeros are A324846.

Positions of ones are A324856.

Cf. A003963, A056239, A112798, A120383, A323440, A324704, A324847, A324849, A324850, A324853.

Sequence in context: A239246 A171700 A162660 * A090330 A332447 A132747

Adjacent sequences:  A324845 A324846 A324847 * A324849 A324850 A324851

KEYWORD

nonn

AUTHOR

Gus Wiseman, Mar 18 2019

STATUS

approved

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Last modified March 29 02:19 EDT 2020. Contains 333104 sequences. (Running on oeis4.)