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A100912 Numbers n such that (3*2^n+1)^2-2 is prime. 0
1, 2, 4, 10, 13, 19, 20, 34, 37, 40, 317, 1258, 1651, 3370, 3640, 3715, 6818, 6925, 8050, 18193 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Next term is > 21000. - Ryan Propper, Sep 03 2005

LINKS

Table of n, a(n) for n=1..20.

S. Harvey, Carol and Kynea Primes.

PROG

(PARI) is(n)=ispseudoprime((3*2^n+1)^2-2) \\ Charles R Greathouse IV, Feb 19 2016

CROSSREFS

Sequence in context: A216814 A180427 A127591 * A174721 A026224 A034233

Adjacent sequences:  A100909 A100910 A100911 * A100913 A100914 A100915

KEYWORD

nonn

AUTHOR

Ray Chandler, Nov 21 2004

EXTENSIONS

One more term from Ryan Propper, Sep 03 2005

STATUS

approved

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Last modified December 9 08:17 EST 2021. Contains 349627 sequences. (Running on oeis4.)