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A325035 Product of sums of the multisets of prime indices of each prime index of 2 * n + 1. 4
1, 1, 2, 2, 1, 3, 3, 2, 4, 3, 2, 4, 4, 1, 4, 5, 3, 4, 4, 3, 6, 5, 2, 5, 4, 4, 4, 6, 3, 7, 5, 2, 6, 8, 4, 5, 6, 4, 6, 6, 1, 9, 8, 4, 5, 6, 5, 6, 6, 3, 7, 6, 4, 6, 10, 4, 6, 8, 3, 8, 9, 6, 8, 11, 5, 5, 6, 2, 7, 8, 5, 9, 8, 4, 7, 6, 4, 10, 12, 4, 8, 9, 6, 8, 9, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

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=0..85.

FORMULA

Fully multiplicative with a(prime(n)) = A056239(n), restricted to odd n.

EXAMPLE

91 has prime indices {4,6} with prime indices {{1,1},{1,2}} with sums {2,3} with product a(45) = 6.

MATHEMATICA

primeMS[n_]:=If[n==1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]];

Table[Times@@Plus@@@primeMS/@primeMS[n], {n, 1, 200, 2}]

CROSSREFS

Cf. A000720, A001055, A001222, A003963, A056239, A112798, A302242, A318949.

Cf. A324926, A325031, A325032, A325033, A325034.

Sequence in context: A274515 A291564 A029266 * A035387 A242308 A011373

Adjacent sequences:  A325032 A325033 A325034 * A325036 A325037 A325038

KEYWORD

nonn

AUTHOR

Gus Wiseman, Mar 25 2019

STATUS

approved

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Last modified April 1 14:52 EDT 2020. Contains 333163 sequences. (Running on oeis4.)