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A361632
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a(n) is the numerator of the median of the prime factors of n with repetition.
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4
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2, 3, 2, 5, 5, 7, 2, 3, 7, 11, 2, 13, 9, 4, 2, 17, 3, 19, 2, 5, 13, 23, 2, 5, 15, 3, 2, 29, 3, 31, 2, 7, 19, 6, 5, 37, 21, 8, 2, 41, 3, 43, 2, 3, 25, 47, 2, 7, 5, 10, 2, 53, 3, 8, 2, 11, 31, 59, 5, 61, 33, 3, 2, 9, 3, 67, 2, 13, 5, 71, 2, 73, 39, 5, 2, 9, 3, 79
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OFFSET
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2,1
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LINKS
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FORMULA
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For p a prime, a(p^k) = p.
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EXAMPLE
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a(12) = 2 since 12 = 2*2*3, and the median of the factors is equal to 2.
a(36) = 5 since 30 = 2*2*3*3, and the median of the factors is equal to 5/2.
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MATHEMATICA
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a[n_]:=Numerator[Median[Flatten[Table[#[[1]], {#[[2]]}] & /@ FactorInteger[n]]]]; Array[a, 78, 2]
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CROSSREFS
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KEYWORD
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nonn,frac
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AUTHOR
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STATUS
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approved
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