%I A094491
%S A094491 223,2104547,2403689,4268233,17620457,21848647,23487311,29205821,
%T A094491 42889591,43458859,47899487,48309017,54666847,61227457,73038689,
%U A094491 81742547,83574457,85031153,87285403,95017003,100339517,103136867
%N A094491 Primes p such that 2^j+p^j are primes for j=0,4,8,128.
%C A094491 Primes of 2^j+p^j form are a generalization of Fermat-primes. This is
strongly supported by the observation that corresponding j-exponents
are apparently powers of 2 like for the 5 known Fermat primes. See
A094473-A094490.
%e A094491 For j=0 1+1=2 is prime; other conditions are: because of p^4+16==prime;
3rd and 4th conditions are as follows: prime=p^8+256 and prime=2^128+p^128.
%t A094491 {ta=Table[0, {100}], u=1}; Do[s0=2;s4=16+Prime[j]^4;s8=256+Prime[j]^8;
s128=2^128+Prime[j]^128 If[PrimeQ[s0]&&PrimeQ[s4]&&PrimeQ[s8]&&PrimeQ[s128],
Print[{j, Prime[j]}];ta[[u]]=Prime[j];u=u+1], {j, 1, 1000000}]
%Y A094491 Cf. A082101, A094473-A094490.
%Y A094491 Sequence in context: A152834 A139233 A153165 this_sequence A162604 A050241
A046296
%Y A094491 Adjacent sequences: A094488 A094489 A094490 this_sequence A094492 A094493
A094494
%K A094491 nonn
%O A094491 1,1
%A A094491 Labos E. (labos(AT)ana.sote.hu), Jun 01 2004
%E A094491 a(5)-a(22) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Oct 12
2008
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