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%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
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