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A207193 Auxiliary function for computing the Carmichael lambda function (A002322). 3
1, 1, 2, 2, 4, 6, 2, 6, 10, 12, 4, 16, 18, 22, 20, 18, 28, 30, 8, 36, 40, 42, 46, 42, 52, 58, 60, 16, 66, 70, 72, 78, 54, 82, 88, 96, 100, 102, 106, 108, 112, 110, 100, 126, 32, 130, 136, 138, 148, 150, 156, 162, 166, 156, 172, 178, 180, 190, 192, 196, 198 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

FORMULA

If p = 2 and e > 2 then a(n)=2^(e-2), otherwise a(n)=(p-1)*p^(e-1), where p^e = A000961(n), the n-th prime power.

PROG

(Haskell)

a207193 1 = 1

a207193 n | p == 2 && e > 2 = 2 ^ (e - 2)

          | otherwise       = (p - 1) * p ^ (e - 1)

          where p = a025473 n; e = a025474 n

CROSSREFS

Cf. A085730, A025473, A025474.

Sequence in context: A191674 A238959 A238972 * A319579 A286631 A286243

Adjacent sequences:  A207190 A207191 A207192 * A207194 A207195 A207196

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Feb 16 2012

STATUS

approved

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Last modified April 22 14:09 EDT 2021. Contains 343177 sequences. (Running on oeis4.)