1,2
Also numbers n such that (49*10^n-13)/9 is prime.
Makoto Kamada, Factorizations of 544...443.
Index entries for primes involving repunits.
Do[ If[ PrimeQ[(49*10^n - 13)/9], Print[n]], {n, 0, 10000}]
Sequence in context: A034418 A034421 A029448 * A116552 A167930 A124285
Adjacent sequences: A103011 A103012 A103013 * A103015 A103016 A103017
more,nonn
Robert G. Wilson v (rgwv(AT)rgwv.com), Jan 18 2005