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%I #22 Mar 03 2020 09:01:28
%S 3,7,11,127,89,8191,30839,363889,178481,2089,4404047,616318177,
%T 164511353,2099863,13264529,20394401
%N Minimum of the greatest prime factors of (i^prime(n)-1)/(i-1), when i runs through all integers in [2, prime(n)].
%C If in the definition "greatest" is replaced with "smallest", then we obtain A035095 (see comment there).
%F a(n) == 1 (mod prime(n)).
%o (PARI) a(n) = {mini = 0; p = prime(n); for (i=2, p, f = factor((i^p-1)/(i-1)); gpf = f[#f~, 1]; if (! mini, mini = gpf, mini = min(mini, gpf));); mini;} \\ _Michel Marcus_, Dec 09 2014
%Y Cf. A035095, A247216.
%K nonn,more
%O 1,1
%A _Vladimir Shevelev_, Nov 27 2014
%E More terms from _Peter J. C. Moses_, Nov 27 2014
%E a(13)-a(14) from _Michel Marcus_, Dec 09 2014
%E a(15)-a(16) from _Jinyuan Wang_, Mar 03 2020