A109346 Primes p such that p + 2 is a brilliant number.

2, 7, 13, 19, 23, 47, 167, 251, 317, 359, 389, 401, 449, 479, 491, 557, 587, 647, 701, 797, 839, 911, 941, 947, 977, 1187, 1217, 1259, 1361, 1367, 1409, 1499, 1511, 1709, 1847, 1889, 1907, 2207, 2417, 2447, 2477, 2579, 2621, 2699, 2879, 2909, 3137, 3719

Offset

1,1

Comments

All terms are Chen primes.

Links

Andrew Howroyd, Table of n, a(n) for n = 1..10000

Prog

(PARI) isok(p)=if(isprime(p), my(f=factor(p+2)); (#f~==1&&f[1, 2]==2) || (#f~==2&&f[1, 2]==1&&f[2, 2]==1&&logint(f[1, 1], 10)==logint(f[2, 1], 10)), 0) \\ Andrew Howroyd, Oct 08 2025

Crossrefs

Subsequence of A109611.

Cf. A078972.

Sequence in context: A063637 A216526 A020623 * A140550 A271114 A138646

Adjacent sequences: A109343 A109344 A109345 * A109347 A109348 A109349

Keyword

base,easy,nonn

Author

Jason Earls, Aug 21 2005

Status

approved