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A075857 Least common multiple of totient and cototient of n. 0
0, 1, 2, 2, 4, 4, 6, 4, 6, 12, 10, 8, 12, 24, 56, 8, 16, 12, 18, 24, 36, 60, 22, 16, 20, 84, 18, 48, 28, 88, 30, 16, 260, 144, 264, 24, 36, 180, 120, 48, 40, 60, 42, 120, 168, 264, 46, 32, 42, 60, 608, 168, 52, 36, 120, 96, 252, 420, 58, 176, 60, 480, 108, 32, 816, 460, 66 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..67.

FORMULA

a(n) = A000010(n)*A051953(n)/A009195(n).

MATHEMATICA

Table[LCM[EulerPhi[n], (n-EulerPhi[n])], {n, 70}] (* Harvey P. Dale, Jun 10 2019 *)

CROSSREFS

Sequence in context: A128923 A153835 A171462 * A023817 A300754 A145392

Adjacent sequences:  A075854 A075855 A075856 * A075858 A075859 A075860

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Oct 15 2002

STATUS

approved

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Last modified January 21 13:47 EST 2020. Contains 331113 sequences. (Running on oeis4.)