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Exactly one of 2^n-3 and 2^n+3 is prime.
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%I #4 Mar 30 2012 18:52:39

%S 1,2,5,7,9,10,14,15,16,18,20,22,24,28,29,30,55,67,84,94,116,122,150,

%T 174,213,221,228,233,266,336,390,452,545,689,694,784,850,1110,1704,

%U 1736,2008,2139,2191,2321,2367,2370,3237,3954,4002,4060,4062,4552,5547,5630

%N Exactly one of 2^n-3 and 2^n+3 is prime.

%C Numbers n which are in A050414 or in A057732 but not in both. [From _R. J. Mathar_, Mar 29 2010]

%e a(1)=1 because 2^1-3=-1 is nonprime and 2^1+3=5 is prime.

%Y Cf. A050414, A057732.

%K nonn

%O 1,2

%A _Juri-Stepan Gerasimov_, Mar 14 2010

%E Corrected by _Charles R Greathouse IV_, Mar 20 2010