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A086865 Numbers n such that 2*10^n+11 is prime. 1
0, 1, 2, 3, 4, 9, 19, 25, 39, 63, 133, 157, 274, 943, 1009, 1353, 7297, 16221, 25256, 30424, 52147 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

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

LINKS

Table of n, a(n) for n=1..21.

MATHEMATICA

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

PROG

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

CROSSREFS

Cf. A081677.

Sequence in context: A014281 A220364 A243902 * A258274 A228126 A192988

Adjacent sequences:  A086862 A086863 A086864 * A086866 A086867 A086868

KEYWORD

hard,more,nonn

AUTHOR

Carl R. White, Aug 20 2003

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

STATUS

approved

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Last modified December 1 16:44 EST 2021. Contains 349430 sequences. (Running on oeis4.)