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A115232 Primes p which can be written in the form 2^i + q^j where i >= 0, j >= 1, q = odd prime.

%I A115232 #21 Aug 04 2018 14:34:44
%S A115232 5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97,
%T A115232 101,103,107,109,113,127,131,137,139,151,157,163,167,173,179,181,191,
%U A115232 193,197,199,211,223,227,229,233,239,241,251,257,263,269,271,277,281
%N A115232 Primes p which can be written in the form 2^i + q^j where i >= 0, j >= 1, q = odd prime.
%C A115232 a(n)=A000040(n+2) for n <= 32, but A000040(35)=149 is a term of A115231;
%C A115232 A115233 is a subsequence; the union with A115231 gives all primes (A000040);
%C A115232 A006512 and A053703 are subsequences.
%t A115232 maxp = 281;
%t A115232 Union[Sort[Reap[Do[p = 2^i + q^j; If[p <= maxp && PrimeQ[p], Sow[p]], {i, 0, Log[2, maxp]//Ceiling}, {j, 1, Log[3, maxp]//Ceiling}, {q, Prime[Range[2, PrimePi[maxp]]]}]][[2, 1]]]] (* _Jean-François Alcover_, Aug 03 2018 *)
%Y A115232 Cf. A000079, A061345.
%Y A115232 Cf. A006512, A053703, A115231, A115233.
%K A115232 nonn
%O A115232 1,1
%A A115232 _Reinhard Zumkeller_, Jan 17 2006
%E A115232 Recomputed (based on recomputation of A115230) by _R. J. Mathar_ and _Reinhard Zumkeller_, Apr 29 2010
%E A115232 Edited by _N. J. A. Sloane_, Apr 30 2010
%E A115232 Terms a(1)=2 and a(2)=3 removed from Data by _Jean-François Alcover_, Aug 03 2018