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%I #11 Dec 27 2019 12:35:22
%S 3,5,7,11,13,17,19,23,31,31,47,41,43,47,79,61,61,317,71,73,89,83,211,
%T 97,101,103,107,109,113,241,131,139,139,1163,151,167,173,167,199,181,
%U 181,197,193,197,199,263,227,227,229,233,241,241,257,283,769,271,271
%N a(n) is the smallest prime such that (a(n) - the n-th prime) is a power of 2.
%C It is only conjectured (see _Cino Hilliard_'s comment at A094076) that this sequence is defined for all n.
%F a(n) = A000040(n) + 2^A094076(n). - _R. J. Mathar_, May 20 2008
%p A094076 := proc(n) local k,p ; k := 0 ; p := ithprime(n) ; while not isprime(p+2^k) do k := k+1 ; od: k ; end: A139758 := proc(n) ithprime(n)+2^A094076(n) ; end: seq(A139758(n),n=1..80) ; # _R. J. Mathar_, May 20 2008
%t sp2[n_]:=Module[{p=Prime[n],k},k=NextPrime[p];While[!IntegerQ[Log[2,k-p]],k=NextPrime[k]];k]; Array[sp2,60] (* _Harvey P. Dale_, Dec 27 2019 *)
%Y Cf. A094076, A033875.
%K nonn
%O 1,1
%A _Leroy Quet_, May 19 2008
%E More terms from _R. J. Mathar_, May 20 2008
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