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A164371 The smaller members of twin prime pairs which are non-Ramanujan primes.

%I A164371 #14 Oct 28 2018 09:14:37
%S A164371 3,5,137,191,197,521,617,1319,1619,1697,1931,1949,2111,2549,2591,2969,
%T A164371 3119,3329,3389,3557,3929,4157,4217,4271,4517,5279,5417,7331,7349,
%U A164371 7757,8009,8429,8837,9011,9281,9437,9857,9929,10007,10037,10457,10529,10859
%N A164371 The smaller members of twin prime pairs which are non-Ramanujan primes.
%C A164371 The terms greater than 5 of the sequence are in A164288.
%H A164371 Dana Jacobsen, <a href="/A164371/b164371.txt">Table of n, a(n) for n = 1..10000</a>
%H A164371 J. Sondow, J. W. Nicholson, and T. D. Noe, <a href="http://arxiv.org/abs/1105.2249"> Ramanujan Primes: Bounds, Runs, Twins, and Gaps</a>, J. Integer Seq. 14 (2011) Article 11.6.2
%F A164371 A001359 \ A104272. - _R. J. Mathar_, Sep 17 2009
%t A164371 nn = 1000;
%t A164371 A001359 = Select[Prime[Range[2 nn]], PrimeQ[# + 2] &];
%t A164371 R = Table[0, {nn}]; s = 0;
%t A164371 Do[If[PrimeQ[k], s++]; If[PrimeQ[k/2], s--]; If[s < nn, R[[s + 1]] = k], {k, Prime[3 nn]}];
%t A164371 A104272 = R + 1;
%t A164371 Complement[A001359, A104272] (* _Jean-François Alcover_, Oct 28 2018, after _T. D. Noe_ in A104272 *)
%o A164371 (Perl) use ntheory ":all"; for (@{twin_primes(1e4)}) { say if !is_ramanujan_prime($_) } # _Dana Jacobsen_, Dec 30 2015
%Y A164371 Cf. A104272, A001359, A164288, A164554
%K A164371 nonn
%O A164371 1,1
%A A164371 _Vladimir Shevelev_, Aug 14 2009, Aug 17 2009
%E A164371 Extended by _R. J. Mathar_, Sep 17 2009