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A319067 a(n) is the least k such that n divides A047994(k) where A047994 is the unitary totient function.

%I A319067 #12 Oct 01 2019 07:28:35
%S A319067 1,3,4,5,11,7,8,9,19,11,23,13,27,24,16,17,103,19,191,33,43,23,47,25,
%T A319067 101,27,76,29,59,31,32,45,67,103,71,37,149,191,79,41,83,43,173,69,112,
%U A319067 47,283,49,197,101,103,53,107,76,253,72,229,59,709,61,367,96,64,85,131
%N A319067 a(n) is the least k such that n divides A047994(k) where A047994 is the unitary totient function.
%H A319067 Amiram Eldar, <a href="/A319067/b319067.txt">Table of n, a(n) for n = 1..10000</a>
%H A319067 József Sándor, <a href="http://www.cs.ubbcluj.ro/~studia-m/2005-2/sandor.pdf">The Unitary Totient Minimum and Maximum Functions</a>, Studia Universitatis Babes-Bolyai Mathematica, Volume L, Number 2, June 2005.
%F A319067 a(p-1) = p for p prime. See Sándor link Theorem 2 p. 95.
%o A319067 (PARI) a047994(n) = prod(i=1, #n=factor(n)~, n[1, i]^n[2, i]-1);
%o A319067 a(n) = my(k=1); while(a047994(k) % n, k++); k;
%Y A319067 Cf. A047994 (unitary totient).
%Y A319067 Cf. A005179 (analog for number of divisors), A061026 (analog for Euler totient), A070982 (analog for sum of divisors).
%K A319067 nonn
%O A319067 1,2
%A A319067 _Michel Marcus_, Sep 09 2018