%I A075723
%S A075723 1,2,3,6,8,15,17,29,30,32,45,48,59,72,74,80,87,128,141,153,155,156,158,
%T A075723 176,182,191,197,210,216,230,273,284,293,305,314,356,366,380,384,399,
%U A075723 402,407,408,410,413,420,435,443,447,450,473,479,497
%N A075723 Numbers n such that 1+n+n^6 is a prime.
%C A075723 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=6 and find several first n's making n_s
a prime (or a probable prime).
%H A075723 T. D. Noe, <a href="b075723.txt">Table of n, a(n) for n=1..1000</a>
%e A075723 15 is OK because at s=6, n=15, n_s=1+n+n^s=11390641 is a prime.
%Y A075723 Cf. A002384, A049407, A049408.
%Y A075723 Sequence in context: A106182 A097097 A095162 this_sequence A138137 A129374
A048809
%Y A075723 Adjacent sequences: A075720 A075721 A075722 this_sequence A075724 A075725
A075726
%K A075723 nonn
%O A075723 1,2
%A A075723 Zak Seidov (zakseidov(AT)yahoo.com), Oct 03 2002
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