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%I M1358 #27 Nov 14 2014 14:36:51
%S 0,1,2,5,9,14,78,81,141,189,498,5070,7349
%N Numbers n such that 2^(2n+1) + 2^(n+1) + 1 is prime.
%C Some of the larger entries may only correspond to probable primes.
%C Next term >= 10^4. - _Jeppe Stig Nielsen_, Mar 28 2014
%D J. Brillhart et al., Factorizations of b^n +- 1. Contemporary Mathematics, Vol. 22, Amer. Math. Soc., Providence, RI, 2nd edition, 1985; and later supplements.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H J. Brillhart et al., <a href="http://dx.doi.org/10.1090/conm/022">Factorizations of b^n +- 1</a>, Contemporary Mathematics, Vol. 22, Amer. Math. Soc., Providence, RI, 3rd edition, 2002.
%H S. S. Wagstaff, Jr., <a href="http://www.cerias.purdue.edu/homes/ssw/cun/index.html">The Cunningham Project</a>
%o (PARI) isok(n) = isprime(2^(2*n+1) + 2^(n+1) + 1); \\ _Michel Marcus_, Mar 28 2014
%Y A108062 is essentially the same sequence.
%K nonn
%O 1,3
%A _N. J. A. Sloane_.
%E More terms from _Rick L. Shepherd_, Sep 07 2002
%E a(13) = 7349 from _Jeppe Stig Nielsen_, Mar 28 2014
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