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A324848
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Number of prime indices of n (counted with multiplicity) that divide n.
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17
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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
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OFFSET
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1,4
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COMMENTS
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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.
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LINKS
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EXAMPLE
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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.
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MATHEMATICA
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Table[Total[Cases[If[n==1, {}, FactorInteger[n]], {p_, k_}:>k/; Divisible[n, PrimePi[p]]]], {n, 100}]
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CROSSREFS
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The version for distinct prime indices is A324852.
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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