1,1

Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime

See A001771 for more terms.

Cf. A158795 [Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Mar 28 2009 ]

Sequence in context: A062127 A160342 A068120 this_sequence A160196 A158518 A083081

Adjacent sequences: A050520 A050521 A050522 this_sequence A050524 A050525 A050526

nonn,nice

N. J. A. Sloane (njas(AT)research.att.com), Dec 29 1999

13 added [Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Mar 28 2009 ]

13 inserted by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Apr 01 2009