%I #14 Sep 18 2024 11:20:44
%S 259,4294967299,18446744073709551619,
%T 340282366920938463463374607431768211459,
%U 115792089237316195423570985008687907853269984665640564039457584007913129639939
%N Composites of the form 2^(2^k)+3.
%D D. M. Burton, Elementary Number Theory, Allyn and Bacon, Inc., Boston, MA, 1976, p. 238.
%H Harry J. Smith, <a href="/A063485/b063485.txt">Table of n, a(n) for n = 1..8</a>
%o (PARI) for(n=0,8,my(x=(2^(2^n)+3)); if(!isprime(x),print1(x, ", ")))
%K nonn
%O 1,1
%A _Jason Earls_, Jul 28 2001
%E Offset changed by _Andrew Howroyd_, Sep 18 2024