A179687 a(n) = 2*q(n)-1 where q(n) is the sequence of records positions of A179686.

3, 5, 7, 19, 27, 37, 47, 53, 67, 95, 101, 103, 107, 131, 149, 173, 181, 191, 227, 239, 263, 293, 311, 317, 349, 359, 367, 373, 383, 419, 461, 463, 479, 509, 547, 557, 587, 613, 619, 647, 653, 677, 701, 743, 751, 773, 787, 821, 841, 863, 887, 947

Offset: 1

Author

Vladimir Shevelev, Jul 24 2010

Keywords

• nonn

Comments

The record positions are q(n) = 2, 3, 4, 10, 14, 19, 24, 27, 34,...

Sequences A179382, A179383, A179480, A179481, A179686 and this sequence show that their terms depend on prime power factorization of 2*n-1. Nevertheless, this question yet is waiting its research. Most likely that almost all terms of this sequence are primes (27, 95, 841,... are not).

Crossrefs

Cf. A179382, A179383, A179480, A179481, A179686

Extensions

Extended beyond a(7) by R. J. Mathar, Dec 04 2011