1,1

Also numbers n such that (77*10^n-41)/9 is prime.

Makoto Kamada, Factorizations of 855...551.

Index entries for primes involving repunits.

Do[ If[ PrimeQ[(77*10^n - 41)/9], Print[n]], {n, 0, 10000}]

Sequence in context: A098898 A098768 A114168 this_sequence A120735 A009727 A168105

Adjacent sequences: A103080 A103081 A103082 this_sequence A103084 A103085 A103086

more,nonn

Robert G. Wilson v (rgwv(AT)rgwv.com), Jan 19 2005