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%I #22 Jul 31 2021 02:09:30
%S 2,11,23,34,59,69,87,95,119,123,129,171,197,239,341,425,455,471,515,
%T 519,635,765,959,1115,1181,1210
%N Numbers m such that 2^m + m is a semiprime.
%F a(n) = 2*k <=> A089535(n) is even <=> A089536(n) = 2 <=> A089537(n) = 4^k/2 + k, and for any prime of this form, there is a term a(n) = 2*k in this sequence. - _M. F. Hasler_, Oct 08 2009
%t Select[Range[1300],PrimeOmega[2^#+#]==2&] (* _Harvey P. Dale_, Dec 18 2014 *)
%Y Cf. A089535, A089536, A089537.
%Y Sequences A165767, A165768, A165769 are the analog for 2^n-n. - _M. F. Hasler_, Oct 08 2009
%K nonn,more
%O 1,1
%A _Jason Earls_, Jul 21 2003
%E More terms from _Ray Chandler_, Nov 08 2003
%E a(15) from _Donovan Johnson_, Mar 06 2008
%E a(16)-a(26) from _Sean A. Irvine_, Oct 27 2009
%E Offset changed to 1 by _Jinyuan Wang_, Jul 30 2021
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