A093943 Primes of the form 8*10^k + 7*R_k, where R_k is the repunit (A002275) of length k.

877, 8777777777, 8777777777777777, 877777777777777777777777777777777, 877777777777777777777777777777777777777, 877777777777777777777777777777777777777777777777777777777777777777

Offset

1,1

Links

Table of n, a(n) for n=1..6.

Makoto Kamada, Prime numbers of the form 877...77.

Index entries for primes involving repunits

Crossrefs

Cf. A002275, A056724 (corresponding k).

Sequence in context: A208787 A208587 A208472 * A252437 A129313 A063051

Adjacent sequences: A093940 A093941 A093942 * A093944 A093945 A093946

Keyword

nonn

Author

Rick L. Shepherd, Apr 17 2004

Status

approved