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A066504
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Sum of n/p^k over all maximal prime-power divisors of n.
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4
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0, 1, 1, 1, 1, 5, 1, 1, 1, 7, 1, 7, 1, 9, 8, 1, 1, 11, 1, 9, 10, 13, 1, 11, 1, 15, 1, 11, 1, 31, 1, 1, 14, 19, 12, 13, 1, 21, 16, 13, 1, 41, 1, 15, 14, 25, 1, 19, 1, 27, 20, 17, 1, 29, 16, 15, 22, 31, 1, 47, 1, 33, 16, 1, 18, 61, 1, 21, 26, 59, 1, 17, 1, 39, 28, 23, 18, 71, 1, 21, 1, 43, 1
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OFFSET
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1,6
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COMMENTS
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REFERENCES
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R. K. Guy, Unsolved Problems in Number Theory, B8.
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LINKS
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EXAMPLE
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a(120) = 120/2^3 + 120/3^1 + 120/5^1 = 15 + 40 + 24 = 79.
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MATHEMATICA
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f[n_ ] := n*Plus @@ (1/#[[1]]^#[[2]] & /@ FactorInteger@n); Array[f, 83] (* Robert G. Wilson v *)
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PROG
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(PARI) { for (n=1, 1000, f=factor(n); a=sum(i=1, matsize(f)[1], n/(f[i, 1]^f[i, 2])); write("b066504.txt", n, " ", a) ) } \\ Harry J. Smith, Feb 18 2010
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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