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a(n) is the least odd prime factor of prime(n)^prime(n)-1.
2

%I #15 Sep 27 2024 07:18:47

%S 3,13,11,3,5,3,10949,3,11,7,3,3,5,3,23,13,29,3,3,5,3,3,41,11,3,5,3,53,

%T 3,7,3,5,17,3,37,3,3,3,83,43,89,3,5,3,7,3,3,3,113,3,29,7,3,5,21589,

%U 131,67,3,3,5,3,73,3,5,3,79,3,3,173,3,11,179,3,3,3,191

%N a(n) is the least odd prime factor of prime(n)^prime(n)-1.

%H Hugo Pfoertner, <a href="/A376431/b376431.txt">Table of n, a(n) for n = 1..6542</a>

%F a(n) = A078701(A088730(n)). - _Michel Marcus_, Sep 27 2024

%o (PARI) a376431(n) = my(pp=prime(n)^prime(n)-1); forprime (p=3, oo, if(pp%p==0, return(p)))

%Y Cf. A078701, A088730, A376432.

%K nonn

%O 1,1

%A _Hugo Pfoertner_, Sep 27 2024