A137460 Prime numbers k such that k^2 +- (k+1) are primes.

3, 5, 17, 71, 101, 131, 677, 839, 857, 1091, 1217, 2129, 2309, 2339, 2957, 3137, 3449, 3989, 4409, 6569, 6719, 6761, 7229, 8501, 8627, 8807, 9521, 9689, 9749, 10589, 10631, 11621, 11777, 11927, 12641, 13487, 13931, 14519, 15527, 15797, 16007

Offset

1,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Formula

A053182 INTERSECT A091567. [R. J. Mathar, Apr 19 2009]

Example

3^2 +- 4 -> (5,13) Primes,
5^2 +- 6 -> (19,31) Primes.

Mathematica

Select[Prime[Range[800]], PrimeQ[ #^2 - (# + 1)] && PrimeQ[ #^2 + (# + 1)] &]

Crossrefs

Cf. A053182, A091567.

Sequence in context: A251737 A125957 A259908 * A319908 A356256 A232238

Adjacent sequences: A137457 A137458 A137459 * A137461 A137462 A137463

Keyword

nonn,easy

Author

Vladimir Joseph Stephan Orlovsky, Apr 21 2008

Extensions

More terms from Karl Hovekamp, Jan 24 2009

Status

approved