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A074466
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a(n) = gcd(n^3, sigma(n^3), phi(n^3)).
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3
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1, 1, 1, 1, 1, 24, 1, 1, 1, 20, 1, 8, 1, 8, 15, 1, 1, 3, 1, 4, 1, 8, 1, 24, 1, 4, 1, 16, 1, 1800, 1, 1, 3, 4, 25, 1, 1, 8, 1, 4, 1, 24, 1, 8, 3, 8, 1, 8, 1, 5, 9, 4, 1, 12, 1, 16, 1, 4, 1, 480, 1, 8, 1, 1, 65, 72, 1, 4, 3, 200, 1, 3, 1, 4, 5, 8, 1, 24, 1, 4, 1, 4, 1, 64, 5, 8, 3, 88, 1, 180, 7, 16, 1
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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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n=10: gcd[1000,2340,400] = 20 = a(10).
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MATHEMATICA
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Table[Apply[GCD, {w^3, DivisorSigma[1, w^3], EulerPhi[w^3]}], {w, 1, 128}]
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PROG
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(Magma) [Gcd(n^3, Gcd(SumOfDivisors(n^3), EulerPhi(n^3))): n in [1..100]]; // Vincenzo Librandi, Sep 20 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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STATUS
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approved
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