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A117315
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Primes within +1 or -1 of a central binomial coefficient C(2n,n).
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1
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2, 3, 5, 7, 19, 71, 251, 3433, 48619, 2704157, 155117519, 35345263801, 2104098963721, 30067266499541039, 6892620648693261354601, 6637553085023755473070799, 410795449442059149332177041, 399608854866744452032002440111, 1520803477811874490019821888415218657
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OFFSET
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0,1
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LINKS
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EXAMPLE
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2 = C(0,0) + 1;
19 = C(6,3) - 1.
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MATHEMATICA
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b = Binomial[2#, # ] & /@ Range@60; Select[ Sort@ Join[b - 1, b, b + 1], PrimeQ@ # &] (* Robert G. Wilson v, Apr 27 2006 *)
Select[Flatten[Table[Binomial[2n, n]+{-1, 1}, {n, 0, 50}]], PrimeQ] (* Harvey P. Dale, Apr 08 2019 *)
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CROSSREFS
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KEYWORD
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easy,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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