A227276 Primes p for which p^2 + p - 1 = q*r (q<r) such that q, r, p^2 + q - 1 and p^2 + r - 1 are primes.

7, 17, 23, 61, 67, 71, 79, 151, 307, 311, 383, 389, 409, 439, 613, 677, 1559, 1627, 1637, 2377, 2719, 2801, 3407, 3821, 4229, 4799, 4919, 5557, 5641, 5743, 5779, 5851, 5867, 6133, 6733, 7121, 7723, 8009, 8527, 8573, 10163, 10729, 11317, 11789, 11987, 14107, 14629, 14653, 14669, 17189, 17401, 18077

Offset

1,1

Links

Peter J. C. Moses, Table of n, a(n) for n = 1..5000

Formula

A226770(a^2(n) - 1) = 3.

Mathematica

Select[Prime[Range[3000]], And@@PrimeQ[#1^2-1+First[#2]]&&Last[#2]=={1, 1}&[#1, Transpose[FactorInteger[#^2+#-1]]]&] (* Peter J. C. Moses, Jul 05 2013 *)

Crossrefs

Cf. A227129, A226770.

Sequence in context: A346656 A057183 A076293 * A300298 A273745 A263264

Adjacent sequences: A227273 A227274 A227275 * A227277 A227278 A227279

Keyword

nonn

Author

Vladimir Shevelev, Jul 04 2013

Extensions

More terms from Peter J. C. Moses.

Status

approved