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A066699
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Numbers k such that binomial(2k,k)+1 is prime.
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17
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1, 2, 4, 7, 12, 19, 22, 38, 46, 62, 68, 72, 84, 166, 184, 214, 340, 348, 445, 517, 692, 817, 1316, 1381, 2554, 2713, 5261, 6209, 6735, 7920, 8207, 8772, 9530, 13075, 13302, 13405, 15002, 16371, 19346, 24151, 26555, 28188, 29235, 33536, 43338, 44048, 65576, 65930, 68666, 78285
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OFFSET
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1,2
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COMMENTS
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a(45) > 40000. All the primes corresponding to terms up to a(44) have been certified by the PFGW software performing the Brillhart-Lehmer-Selfridge N-1 test. - Giovanni Resta, Apr 05 2017
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REFERENCES
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Aigner and Ziegler. Proofs from the Book, 2nd edition. Springer-Verlag, 2001.
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LINKS
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EXAMPLE
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C(4,2) + 1 = 7, a prime; so 2 is a term of the sequence.
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MATHEMATICA
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Do[If[PrimeQ[Binomial[2 a, a]+1], a >>>"C:\prime.txt"], {a, 1, 20000}] (* Ed Pegg Jr *)
Select[Range[1, 5 * 10^2], PrimeQ[Binomial[2* #, # ] + 1] &]
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PROG
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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