%I A049408
%S A049408 1,2,5,6,9,11,12,14,24,26,32,36,44,47,60,69,72,74,77,89,90,102,107,119,
%T A049408 126,131,146,147,159,162,170,171,186,191,197,204,206,219,239,240,252,
%U A049408 266,284,285,290,296,300,324,347,351,362,384,426,437,459,465,470
%N A049408 Numbers n such that n^4+n+1 is prime.
%C A049408 For s = 5,8,11,14,17,20,..., n_s=1+n+n^s is always composite for any
n>1. Also for n=1, n_s=3 is a prime for any s. Here we consider the
case s=4.
%H A049408 T. D. Noe, <a href="b049408.txt">Table of n, a(n) for n=1..1000</a>
%e A049408 26 is OK because at s=4, n=26, n_s=1+n+n^s=457003 is a prime.
%o A049408 (PARI) for(n=1,1000,if(isprime(1+n+n^4),print1(n",")))
%Y A049408 Cf. A002384, A075723, A049407.
%Y A049408 Sequence in context: A166087 A153143 A075724 this_sequence A138970 A046160
A033161
%Y A049408 Adjacent sequences: A049405 A049406 A049407 this_sequence A049409 A049410
A049411
%K A049408 nonn
%O A049408 1,2
%A A049408 N. J. A. Sloane (njas(AT)research.att.com).
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