OFFSET

1,1

COMMENTS

2^a(n) - 1 is in A001123.

a(12) >= 21701. - Max Alekseyev, Feb 08 2024

LINKS

Discussion titled Conjecture about multiplicative order of 3 modulo a Mersenne prime, (postings in mersenneforum.org), starting May 14 2006.

MATHEMATICA

Select[Prime@Range[98], PrimitiveRoot[2^# - 1] == 3 &]

CROSSREFS

KEYWORD

hard,more,nonn

AUTHOR

Arkadiusz Wesolowski, Nov 20 2012

EXTENSIONS

a(9)-a(11) from Max Alekseyev, Feb 07 2024

STATUS

approved