A051616 Primes p for which A051614(p) is 3 but are not Sophie Germain primes.

17, 47, 71, 107, 137, 167, 197, 227, 257, 263, 317, 347, 401, 449, 467, 557, 569, 587, 599, 617, 647, 677, 701, 797, 827, 839, 857, 863, 881, 887, 929, 947, 971, 977, 1061, 1097, 1181, 1187, 1217, 1259, 1277, 1283, 1307, 1367, 1373, 1427, 1433, 1487, 1493

Offset: 1

Author

Labos Elemer

Keywords

• nonn

Crossrefs

Cf. A000945, A051309-A051335, A005384 (Sophie Germain primes).

Formula

p values so that F(2*p*F(2*p+1)+1)=3 and 2p+1 is not prime; F(x) is the least prime divisor of x.

Extensions

Name corrected by Sean A. Irvine, Sep 22 2021