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%I #27 Aug 24 2020 23:25:02
%S 1,2,337536,585106,602056,2071960,11861410,20706120,54020170,72696726,
%T 87584646,89445636,95895930,98583340,98595070,112204200,205739220,
%U 279448296,292582836,337969690,349672456,432972780,437874186,474186576,479631880,483333426,621777466,643697776
%N Numbers b such that b+1, b^2+1, b^4+1, b^8+1 and b^16+1 are primes.
%C The first term greater than 1 such that b^32+1 is also a prime is a(173) = 7072833120, see A235390. - _Alex Ratushnyak_, Jan 02 2014, comment extended by _Jeppe Stig Nielsen_, Aug 18 2020
%C The term a(2)=2 corresponds to the five classical Fermat primes. - _Jeppe Stig Nielsen_, Aug 18 2020
%H Jeppe Stig Nielsen, <a href="/A070694/b070694.txt">Table of n, a(n) for n = 1..1000</a> (calculated by Yves Gallot).
%H Yves Gallot, <a href="https://github.com/galloty/GFP/">GFP (Generalized Fermat Progressions) / gfp5</a>, software for calculating this sequence.
%t Do[ If[ PrimeQ[n + 1] && PrimeQ[n^2 + 1] && PrimeQ[n^4 + 1] && PrimeQ[n^8 + 1] && PrimeQ[n^16 + 1], Print[n]], {n, 1, 10^7}]
%Y Cf. A090872, A235390.
%K nonn
%O 1,2
%A _Robert G. Wilson v_, May 13 2002
%E a(7)-a(24) from _Donovan Johnson_, Dec 02 2009
%E a(25)-a(28) from _Alex Ratushnyak_, Jan 02 2014
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