A086865 Numbers n such that 2*10^n+11 is prime.

0, 1, 2, 3, 4, 9, 19, 25, 39, 63, 133, 157, 274, 943, 1009, 1353, 7297, 16221, 25256, 30424, 52147

Offset: 1

Author

Carl R. White, Aug 20 2003

Keywords

• hard
• more
• nonn

Comments

a(22) > 10^5. - Robert Price, Jan 10 2015

Crossrefs

Cf. A081677.

Programs

Mathematica

Do[ If[ PrimeQ[2*10^n + 11], Print[n]], {n, 0, 4800}]

PARI

is(n)=isprime(2*10^n+11) \\ Charles R Greathouse IV, Sep 27 2016

Extensions

Edited and extended by Robert G. Wilson v, Aug 25 2003

Term a(13) (had been listed as 254) corrected by Jon E. Schoenfield, Jul 13 2010

a(17)-a(21) from Robert Price, Jan 10 2015