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A166142
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Row products of A166141; Product of such divisors of n that are squarefree and have an even number of prime factors.
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5
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1, 1, 1, 1, 1, 6, 1, 1, 1, 10, 1, 6, 1, 14, 15, 1, 1, 6, 1, 10, 21, 22, 1, 6, 1, 26, 1, 14, 1, 900, 1, 1, 33, 34, 35, 6, 1, 38, 39, 10, 1, 1764, 1, 22, 15, 46, 1, 6, 1, 10, 51, 26, 1, 6, 55, 14, 57, 58, 1, 900, 1, 62, 21, 1, 65, 4356, 1, 34, 69, 4900, 1, 6, 1, 74, 15, 38, 77, 6084, 1, 10
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OFFSET
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1,6
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LINKS
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FORMULA
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EXAMPLE
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For n = 30 = 2*3*5, all its divisors [1, 2, 3, 5, 6, 10, 15, 30] are squarefree, but only 1, 6, 10 and 15 have an even number of prime factors, thus a(30) = 1*6*10*15 = 900. - Antti Karttunen, Aug 06 2018
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PROG
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(PARI) A166142(n) = { my(m=1); fordiv(n, d, m *= if(moebius(d) > 0, d, 1)); (m); }; \\ Antti Karttunen, Aug 06 2018
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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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