cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A215961 Number of primes of the form 1 + b^8192 for 1 < b < 10^n.

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%I A215961 #9 Aug 30 2012 13:25:02
%S A215961 0,0,0,0,3,74,621
%N A215961 Number of primes of the form 1 + b^8192 for 1 < b < 10^n.
%C A215961 Primes 1 + b^8192 are a form of generalized Fermat primes. It is conjectured that a(n) is asymptotic to 0.00103368*li(10^n).
%H A215961 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 A215961 Yves Gallot, <a href="http://yves.gallot.pagesperso-orange.fr/primes/stat.html">How many prime numbers appear in a sequence ?</a>
%H A215961 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>
%H A215961 Mersenne Wiki, <a href="http://mersennewiki.org/index.php/User:Merfighters/listtest">Table of known GF primes b^n+1 where n (exponent) is at least 8192</a>
%e A215961 a(5) = 3 because the generalized Fermat numbers F_13(b) where b<10^5 are prime only for b = 30406, 71852, 85654.
%o A215961 (PARI) a(n) = sum(b=1, 10^n/2-1, isprime((2*b)^8192+1))
%Y A215961 Cf. A215047, A215048, A215049, A215050, A215051, A215057, A215058, A215698, A215699, A215700.
%K A215961 nonn,more
%O A215961 1,5
%A A215961 _Henryk Dabrowski_, Aug 29 2012