1,1

Also numbers n such that (73*10^n-1)/9 is prime.

The next term is > 10000. - Hugo Pfoertner (hugo(AT)pfoertner.org), Oct 21 2004

Makoto Kamada, Factorizations of 811...11

Index entries for primes involving repunits

Do[ If[ PrimeQ[ 8*10^n + (10^n-1)/9], Print[n]], {n, 0, 5000}]

Sequence in context: A099006 A041659 A042043 this_sequence A143876 A126203 A126655

Adjacent sequences: A056719 A056720 A056721 this_sequence A056723 A056724 A056725

hard,nonn

Robert G. Wilson v (rgwv(AT)rgwv.com), Aug 11 2000