A093166 Primes of the form 80*R_k + 3, where R_k is the repunit (A002275) of length k.

3, 83, 883, 88883, 88888883, 888888883, 888888888888883, 888888888888888888888888888888888888888888888888883, 88888888888888888888888888888888888888888888888888888888888888888888883

Offset

1,1

Comments

Primes of the form (8*10^k - 53)/9. - Vincenzo Librandi, Nov 16 2010

Links

Table of n, a(n) for n=1..9.

Makoto Kamada, Prime numbers of the form 88...883.

Index entries for primes involving repunits

Mathematica

Select[Table[FromDigits[PadLeft[{3}, n, 8]], {n, 80}], PrimeQ] (* Harvey P. Dale, Sep 21 2013 *)

Crossrefs

Cf. A002275, A056694 (corresponding k), A099422.

Sequence in context: A036943 A178001 A173811 * A111648 A013518 A166241

Adjacent sequences: A093163 A093164 A093165 * A093167 A093168 A093169

Keyword

nonn

Author

Rick L. Shepherd, Mar 26 2004

Status

approved