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Primes p for which A051614(p) is 3 but are not Sophie Germain primes.
6

%I #11 Sep 23 2021 02:03:48

%S 17,47,71,107,137,167,197,227,257,263,317,347,401,449,467,557,569,587,

%T 599,617,647,677,701,797,827,839,857,863,881,887,929,947,971,977,1061,

%U 1097,1181,1187,1217,1259,1277,1283,1307,1367,1373,1427,1433,1487,1493

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

%F 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.

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

%K nonn

%O 1,1

%A _Labos Elemer_

%E Name corrected by _Sean A. Irvine_, Sep 22 2021