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%I #15 Apr 28 2022 13:35:08
%S 149,151,179,181,227,229,239,241,347,349,431,433,569,571,599,601,641,
%T 643,821,823,1019,1021,1049,1051,1061,1063,1427,1429,1487,1489,1607,
%U 1609,1787,1789,1997,1999,2081,2083,2129,2131,2237,2239,2267,2269,2657,2659,2687,2689,2711,2713,2789,2791,2999,3001,3167,3169,3257,3259,3299,3301,3359,3361,3527,3529,3539,3541
%N Twin Ramanujan primes.
%H Amiram Eldar, <a href="/A190654/b190654.txt">Table of n, a(n) for n = 1..10000</a>
%F a(2n-1) = A178127(n).
%F a(2n) = A178127(n) + 2.
%t FasterRamanujanPrimeList[n_] := With[{T = Table[{k, PrimePi[k] - PrimePi[k/2]}, {k, Prime[3*n]}]}, Table[1 + First[Last[Select[T, Last[#] == i - 1 &]]], {i, 1, n}]]; Select[Partition[FasterRamanujanPrimeList[222], 2, 1], First[#] == Last[#] - 2 &]//Flatten (* _Robert P. P. McKone_, Mar 21 2022 *)
%Y Cf. A178127 (lesser of twin Ramanujan primes).
%K nonn
%O 1,1
%A _Jonathan Sondow_, May 16 2011
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