A186538 Numbers n>0 such that 666*10^n+7 is prime.

25, 26, 28, 33, 49, 80, 81, 133, 179, 202, 222, 271, 411, 588, 682, 1039, 2403, 5802, 11544, 12484, 41047, 46396

Offset

1,1

Comments

Some of the larger entries may only correspond to probable primes.

Links

Table of n, a(n) for n=1..22.

Chris Caldwell, The Prime Glossary, Beastly prime

G. L. Honaker, Jr. and Chris Caldwell, Prime Curios! 66600...00007 (28-digits)

Henri & Renaud Lifchitz, PRP Records

R. Ondrejka, The Top Ten: a Catalogue of Primal Configurations

Mathematica

Select[Range[10^3], PrimeQ[666*10^# + 7] &] (* Arkadiusz Wesolowski, Sep 08 2011 *)

Crossrefs

Cf. A186086.

Sequence in context: A140058 A199992 A242221 * A340271 A003996 A132415

Adjacent sequences: A186535 A186536 A186537 * A186539 A186540 A186541

Keyword

nonn,base,more

Author

Arkadiusz Wesolowski, Feb 23 2011

Extensions

a(21) from Arkadiusz Wesolowski, May 25 2011

a(22) from Arkadiusz Wesolowski, May 28 2011

Status

approved