1,2

Makoto Kamada, Factorizations of 500...009.

Sabin Tabiraca and Kieran Reynolds, Lacunary Prime Numbers.

Index entries for primes involving repunits.

Do[ If[ PrimeQ[5*10^n + 3], Print[n]], {n, 0, 10000}]

Sequence in context: A025071 A049908 A135568 this_sequence A102016 A002363 A041457

Adjacent sequences: A103001 A103002 A103003 this_sequence A103005 A103006 A103007

more,nonn

Robert G. Wilson v (rgwv(AT)rgwv.com), Jan 18 2005