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%I #38 Oct 18 2018 11:02:41
%S 0,3,22,146,1062,8963,74951,651537,5740807,51389252
%N Number of primes of the form 1 + b^32 for 1 < b < 10^n.
%C Primes 1 + b^32 are a form of generalized Fermat primes.
%C It is conjectured that a(n) is asymptotic to 0.112903*li(10^n).
%H Yves Gallot, <a href="http://yves.gallot.pagesperso-orange.fr/primes/results.html">Status of the smallest base values yielding Generalized Fermat primes</a>
%H Yves Gallot, <a href="http://yves.gallot.pagesperso-orange.fr/primes/stat.html">How many prime numbers appear in a sequence ?</a>
%H Yves Gallot, <a href="http://yves.gallot.pagesperso-orange.fr/papers/ccdgfpn.html">A Problem on the Conjecture Concerning the Distribution of Generalized Fermat Prime numbers (a new method for the search for large primes)</a>
%F a(n) = A214956(32*n) - 1.
%e a(2) = 3 because the Fermat numbers F_5(b) where b<10^2 are prime only for b = 30, 54, 96.
%t Table[Length[Select[Range[2,10^n-1]^32 + 1, PrimeQ]], {n, 4}] (* _T. D. Noe_, Aug 01 2012 *)
%o (PARI) a(n) = sum(b=1, 10^n/2-1, isprime((2*b)^32+1))
%Y Cf. A214956, A215047, A215048, A215049, A215050, A215057, A215058
%K nonn,more
%O 1,2
%A _Henryk Dabrowski_, Aug 01 2012
%E a(9)-a(10) from _Chai Wah Wu_, Oct 18 2018
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