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a(n) is the smallest primitive root of A133433(n).
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%I #14 May 26 2019 19:42:12

%S 2,3,5,6,7,10,11,12,18,20,24,40,42,45,48,54,72,80,96

%N a(n) is the smallest primitive root of A133433(n).

%C Also with an initial 1, numbers k such that A023048(k) set a new record.

%C If A023048(108) != 0 (which is implied assuming generalized Artin's conjecture) then the next term of this sequence is 108.

%C Conjecturally 11 is the largest prime in this sequence, 42 is the largest squarefree term, and 45 is the largest odd term.

%H Tomás Oliveira e Silva, <a href="http://sweet.ua.pt/tos/p_roots.html">Least primitive root of prime numbers</a>

%e The smallest prime with least primitive root 11 is 643, and the smallest prime with least primitive root 2, 3, 5, ..., 10 are all < 643, so 11 is a term.

%e The smallest prime with least primitive root 45 is 95525767, and the smallest prime with least primitive root 2, 3, 5, ..., 44 are all < 95525767, so 45 is a term.

%e 13 is not a term since the smallest prime with least primitive root 13 is 457, but the smallest prime with least primitive root 12 is 4111, which is larger than 457.

%Y Cf. A023048, A133433.

%K nonn,hard,more

%O 1,1

%A _Jianing Song_, Aug 22 2018