%I #6 Dec 19 2018 19:02:53

%S 3,2,3,2,5,2,3,2,3,2,5,2,3,2,3,2,7,2,3,2,3,2,5,2,3,2,3,2,7,2,3,2,3,2,

%T 5,2,3,2,3,2,13,2,3,2,3,2,5,2,3,2,3,2,5,2,3,2,3,2,7,2,3,2,3,2,5,2,3,2,

%U 3,2,5,2,3,2,3,2,7,2,3,2,3,2,5,2,3,2,3,2,7,2,3,2,3,2,5,2,3,2,3,2,7,2

%N Least prime factor of n^n-1.

%C If n is odd then a(n)=2; also, if n is even and not divisible by 3 then a(n)=3. - _Zak Seidov_, Mar 03 2006

%H Antti Karttunen, <a href="/A116895/b116895.txt">Table of n, a(n) for n = 2..16384</a>

%e 6^6-1=5*7*31*43, so a(6)=5.

%t Table[FactorInteger[GCD[n^n-1, 200! ]][[1,1]], {n, 2, 130}]

%o (PARI) A116895(n) = { my(k=(n^n)-1); forprime(p=2, ,if(!(k%p),return(p))); }; \\ _Antti Karttunen_, Dec 19 2018

%Y Cf. A006486, A007571, A048861.

%K nonn

%O 2,1

%A _Giovanni Resta_, Mar 02 2006