A074466 - OEIS

A074466

a(n) = gcd(n^3, sigma(n^3), phi(n^3)).

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

1,6

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

FORMULA

a(n) = A074389(n^3).

EXAMPLE

n=10: gcd[1000,2340,400] = 20 = a(10).

MATHEMATICA

Table[Apply[GCD, {w^3, DivisorSigma[1, w^3], EulerPhi[w^3]}], {w, 1, 128}]

GCD[#, DivisorSigma[1, #], EulerPhi[#]]&/@(Range[100]^3) (* Harvey P. Dale, Nov 03 2024 *)