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Numbers n such that 2^(2n+1) - 2^(n+1) + 1 is a prime.
(Formerly M3098)
3

%I M3098 #22 Sep 13 2019 20:43:59

%S 1,3,23,36,39,56,75,83,119,120,176,183,228,683,1520

%N Numbers n such that 2^(2n+1) - 2^(n+1) + 1 is a prime.

%C These numbers satisfy A100014(n)=2. - _Michel Marcus_, Mar 07 2013

%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>

%t Do[ If[ PrimeQ[ 2^(2n + 1) - 2^(n + 1) + 1 ], Print[n] ], {n, 1, 4000} ]

%Y Cf. A007670.

%Y Indices of primes in A092440. For the actual primes see A325914.

%K nonn

%O 1,2

%A _N. J. A. Sloane_, _Robert G. Wilson v_