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A190654
Twin Ramanujan primes.
3
149, 151, 179, 181, 227, 229, 239, 241, 347, 349, 431, 433, 569, 571, 599, 601, 641, 643, 821, 823, 1019, 1021, 1049, 1051, 1061, 1063, 1427, 1429, 1487, 1489, 1607, 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
OFFSET
1,1
LINKS
FORMULA
a(2n-1) = A178127(n).
a(2n) = A178127(n) + 2.
MATHEMATICA
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 *)
CROSSREFS
Cf. A178127 (lesser of twin Ramanujan primes).
Sequence in context: A248412 A182874 A268428 * A308895 A100723 A316589
KEYWORD
nonn
AUTHOR
Jonathan Sondow, May 16 2011
STATUS
approved