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A319067 a(n) is the least k such that n divides A047994(k) where A047994 is the unitary totient function. 1
1, 3, 4, 5, 11, 7, 8, 9, 19, 11, 23, 13, 27, 24, 16, 17, 103, 19, 191, 33, 43, 23, 47, 25, 101, 27, 76, 29, 59, 31, 32, 45, 67, 103, 71, 37, 149, 191, 79, 41, 83, 43, 173, 69, 112, 47, 283, 49, 197, 101, 103, 53, 107, 76, 253, 72, 229, 59, 709, 61, 367, 96, 64, 85, 131 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

József Sándor, The Unitary Totient Minimum and Maximum Functions, Studia Universitatis Babes-Bolyai Mathematica, Volume L, Number 2, June 2005.

FORMULA

a(p-1) = p for p prime. See Sándor link Theorem 2 p. 95.

PROG

(PARI) a047994(n) = prod(i=1, #n=factor(n)~, n[1, i]^n[2, i]-1);

a(n) = my(k=1); while(a047994(k) % n, k++); k;

CROSSREFS

Cf. A047994 (unitary totient).

Cf. A005179 (analog for number of divisors), A061026 (analog for Euler totient), A070982 (analog for sum of divisors).

Sequence in context: A225906 A332790 A329524 * A224503 A128920 A006288

Adjacent sequences:  A319064 A319065 A319066 * A319068 A319069 A319070

KEYWORD

nonn

AUTHOR

Michel Marcus, Sep 09 2018

STATUS

approved

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Last modified April 5 13:26 EDT 2020. Contains 333241 sequences. (Running on oeis4.)