A168166 Primes which are the concatenation of a prime p and 2p+1.

37, 1123, 1327, 2347, 3163, 59119, 71143, 79159, 101203, 113227, 151303, 163327, 173347, 193387, 199399, 229459, 269539, 281563, 331663, 359719, 383767, 431863, 491983, 5091019, 5691139, 6611323, 7091419, 7191439, 8291659, 8391679, 8531707

Offset

1,1

Comments

The corresponding primes p are listed in A168164.

Contains the subsequence A168165 (where p is restricted to be a Sophie Germain prime).

Links

Table of n, a(n) for n=1..31.

Prog

(PARI) forprime(p=1, 999, isprime(eval(Str(p, 2*p+1))) & print1(p, 2*p+1, ", "))

Crossrefs

Sequence in context: A101631 A005390 A253245 * A168165 A340539 A219309

Adjacent sequences: A168163 A168164 A168165 * A168167 A168168 A168169

Keyword

base,nonn

Author

M. F. Hasler, Nov 25 2009

Status

approved