

A093165


Primes of the form 70*R_n + 3, where R_n is the repunit (A002275) of length n.


4




OFFSET

1,1


COMMENTS

Primes of the form (7*10^n  43)/9.  Vincenzo Librandi, Nov 16 2010
The next term, a(9), has 264 digits.  Harvey P. Dale, Jul 19 2012


LINKS

Table of n, a(n) for n=1..8.
Makoto Kamada, Prime numbers of the form 77...773.
Index entries for primes involving repunits


MATHEMATICA

Select[Table[FromDigits[PadLeft[{3}, n, 7]], {n, 500}], PrimeQ] (* Harvey P. Dale, Jul 19 2012 *)


CROSSREFS

Cf. A056689 (corresponding n), A099420.
Sequence in context: A060883 A162601 A173807 * A189306 A012810 A020517
Adjacent sequences: A093162 A093163 A093164 * A093166 A093167 A093168


KEYWORD

nonn


AUTHOR

Rick L. Shepherd, Mar 26 2004


STATUS

approved



