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%I #21 Mar 25 2017 06:39:10
%S 3,13,31,55987,12207031,16148168401,50544702849929377,
%T 109912203092239643840221,11111111111111111111111,
%U 7369130657357778596659,568972471024107865287021434301977158534824481,388230138454493
%N Maximum of the smallest prime factors of (i^prime(n)-1)/(i-1), when i runs through all integers in [2, prime(n)].
%C If in the definition "maximum" is replaced with "minimum," then we obtain A035095 (see comment there).
%F a(n) == 1 (mod prime(n)).
%p with(numtheory):
%p a:= n-> max(seq(min(factorset(
%p (i^ithprime(n)-1)/(i-1))[]), i=2..ithprime(n))):
%p seq(a(n), n=1..10); # _Alois P. Heinz_, Dec 06 2014
%t a[n_] := Max[Table[Min[FactorInteger[(i^Prime[n]-1)/(i-1)][[All, 1]]], {i, 2, Prime[n]}]];
%t Table[a[n], {n, 1, 12}] (* _Jean-François Alcover_, Mar 25 2017, after _Alois P. Heinz_ *)
%Y Cf. A020639, A035095.
%K nonn
%O 1,1
%A _Vladimir Shevelev_, Nov 26 2014
%E More terms from _Peter J. C. Moses_, Nov 26 2014