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%I #47 Nov 02 2020 09:08:44
%S 2,2,5,11,17,37,67,131,257,521,1031,2053,4099,8209,16411,32771,65537,
%T 131101,262147,524309,1048583,2097169,4194319,8388617,16777259,
%U 33554467,67108879,134217757,268435459,536870923,1073741827,2147483659
%N Smallest prime >= 2^n.
%H Jinyuan Wang, <a href="/A104080/b104080.txt">Table of n, a(n) for n = 0..1000</a>
%F a(n) = A014210(n), n <> 1. - _R. J. Mathar_, Oct 14 2008
%F Sum_{n >= 0) 1/a(n) = A338475 + 1/6 = 1.4070738... (because 1/6 = 1/2 - 1/3). - _Bernard Schott_, Nov 01 2020
%t Join[{2,2},NextPrime[#]&/@(2^Range[2,40])] (* _Harvey P. Dale_, Jan 26 2011 *)
%t NextPrime[2^Range[0,50]-1] (* _Vladimir Joseph Stephan Orlovsky_, Apr 11 2011 *)
%o (PARI) g(n,b=2) = for(x=0,n,print1(nextprime(b^x)","))
%o (PARI) a(n) = nextprime(2^n); \\ _Michel Marcus_, Nov 01 2020
%Y Cf. A014210, A104081, A338475.
%K easy,nonn
%O 0,1
%A _Cino Hilliard_, Mar 03 2005
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