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A325034 Sum of products of the multisets of prime indices of each prime index of n. 10
0, 1, 1, 2, 2, 2, 1, 3, 2, 3, 3, 3, 2, 2, 3, 4, 4, 3, 1, 4, 2, 4, 4, 4, 4, 3, 3, 3, 3, 4, 5, 5, 4, 5, 3, 4, 2, 2, 3, 5, 6, 3, 4, 5, 4, 5, 6, 5, 2, 5, 5, 4, 1, 4, 5, 4, 2, 4, 7, 5, 4, 6, 3, 6, 4, 5, 8, 6, 5, 4, 3, 5, 8, 3, 5, 3, 4, 4, 5, 6, 4, 7, 9, 4, 6, 5, 4 (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
FORMULA
Totally additive with a(prime(n)) = A003963(n).
EXAMPLE
94 has prime indices {1,15} with prime indices {{},{2,3}} with products {1,6} with sum a(94) = 7.
MATHEMATICA
primeMS[n_]:=If[n==1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]];
Table[Plus@@Times@@@primeMS/@primeMS[n], {n, 100}]
CROSSREFS
Sequence in context: A325121 A064659 A349520 * A275853 A324100 A127953
KEYWORD
nonn
AUTHOR
Gus Wiseman, Mar 25 2019
STATUS
approved

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Last modified April 25 07:53 EDT 2024. Contains 371964 sequences. (Running on oeis4.)