A117315 Primes within +1 or -1 of a central binomial coefficient C(2n,n).

2, 3, 5, 7, 19, 71, 251, 3433, 48619, 2704157, 155117519, 35345263801, 2104098963721, 30067266499541039, 6892620648693261354601, 6637553085023755473070799, 410795449442059149332177041, 399608854866744452032002440111, 1520803477811874490019821888415218657

Offset

0,1

Links

Harvey P. Dale, Table of n, a(n) for n = 0..47

Example

2 = C(0,0) + 1;
19 = C(6,3) - 1.

Mathematica

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 *)

Crossrefs

Cf. A000040, A000984.

Sequence in context: A235620 A289756 A236303 * A158473 A048420 A048405

Adjacent sequences: A117312 A117313 A117314 * A117316 A117317 A117318

Keyword

easy,nonn

Author

Greg Huber, Apr 24 2006

Extensions

More terms from Robert G. Wilson v, Apr 27 2006

More terms from Harvey P. Dale, Apr 08 2019

Status

approved