1,1

Also numbers n such that (41*10^n+31)/9 is prime.

Makoto Kamada, Factorizations of 455...559.

Index entries for primes involving repunits.

Do[ If[ PrimeQ[(41*10^n + 31)/9], Print[n]], {n, 0, 10000}]

Sequence in context: A069257 A133885 A064929 this_sequence A020880 A046467 A132184

Adjacent sequences: A102990 A102991 A102992 this_sequence A102994 A102995 A102996

more,nonn

Robert G. Wilson v (rgwv(AT)rgwv.com), Jan 17 2005