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A193526
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Sum of even divisors of sopf(n).
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1
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0, 2, 0, 2, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 14, 2, 0, 0, 0, 0, 12, 0, 0, 0, 0, 0, 0, 0, 0, 12, 0, 2, 16, 0, 24, 0, 0, 0, 30, 0, 0, 24, 0, 0, 14, 0, 0, 0, 0, 0, 36, 0, 0, 0, 30, 0, 24, 0, 0, 12, 0, 0, 12, 2, 26, 30, 0, 0, 28, 16, 0, 0, 0, 0, 14, 0, 26, 26, 0, 0
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OFFSET
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1,2
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COMMENTS
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Sopf(n) is the sum of the distinct primes dividing n (A008472).
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LINKS
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FORMULA
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MATHEMATICA
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Table[Total[Select[Divisors[Plus @@ First[Transpose[FactorInteger[n]]]], EvenQ[#] &]], {n, 100}]
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PROG
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(PARI)
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CROSSREFS
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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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