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%I #12 Sep 08 2022 08:45:07
%S 1,3,8,21,23,26,33,36,38,45,51,57,69,71,78,92,107,117,149,156,170,176,
%T 179,195,209,216,219,224,261,293,321,341,359,374,378,386,390,404,410,
%U 413,420,474,492,507,516,546,569,572,582,621,632,683,767,783,789,809
%N 1+n+n^s is a prime, s=10.
%C For s = 5,8,11,14,17,20,..., n_s=1+n+n^s is always composite for any n>1. Also at n=1, n_s=3 is a prime for any s. So it is interesting to consider only the cases of s =/= 5,8,11,14,17,20,... and n>1. Here i consider the case s=10 and find several first n's making n_s a prime (or a probable prime).
%H Vincenzo Librandi, <a href="/A075719/b075719.txt">Table of n, a(n) for n = 1..3300</a>
%e 3 is OK because at s=10, n=3, n_s=1+n+n^s=59053 is a prime.
%t Select[Range[1000], PrimeQ[1 + # + #^10] &] (* _Vincenzo Librandi_, Jul 28 2014 *)
%o (PARI) for(n=1,1000,if(isprime(1+n+n^10),print1(n",")))
%o (Magma) [n: n in [0..1000] | IsPrime(s) where s is 1+n+n^10]; // _Vincenzo Librandi_, Jul 28 2014
%Y Cf. A002384, A075718, A075720.
%K nonn,easy
%O 1,2
%A _Zak Seidov_, Oct 03 2002
%E More terms from _Ralf Stephan_, Apr 05 2003
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