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%I #32 Sep 02 2014 16:46:43
%S 3,3,3,1,7,3,7,1,3,3,9,1,33,7,9,1,43,17,27,1,9,3,7,1,55,47,285,1,27,3,
%T 39,1,43,117,163,1,63,255,15,1,87,3,43,1,187,77,37,1,105,45,25,1,99,
%U 305,79,1,3,27,903,1,127,293,255,1,27,27,435,1,207,143,127,1,117,295,1159,1,477
%N Least integer m > 1 such that 4 + m^n is prime or 1 if only 4 + 1^n is prime.
%C If n is a multiple of 4 then 4 + m^n is prime iff m = 1.
%C 4 + m^(4*x) = (m^(2*x)-2*m^x+2) * (m^(2*x)+2*m^x+2). - _Jens Kruse Andersen_, Sep 02 2014
%H Zak Seidov and Jens Kruse Andersen, <a href="/A243095/b243095.txt">Table of n, a(n) for n = 1..1000</a> (first 200 terms from Zak Seidov)
%o (PARI)
%o a(n)=if(n%4==0,return(1));m=2;while(!ispseudoprime(4+m^n),m++);return(m)
%o vector(100,n,a(n)) \\ _Derek Orr_, Aug 29 2014
%Y Cf. A007591, A073573, A125260, A172367, A246519.
%K nonn
%O 1,1
%A _Zak Seidov_, Aug 29 2014
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