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A100911 Numbers k such that (3*2^k - 1)^2 - 2 is prime. 0
0, 1, 4, 6, 15, 21, 25, 70, 129, 399, 511, 856, 9574, 14479, 17649, 27054, 28296, 32796, 38176 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Next term > 100000.

a(1)-a(12) have been proved with PARI's ECPP; all subsequent terms correspond to BPSW PRPs. - Lucas A. Brown, Mar 28 2021

LINKS

Table of n, a(n) for n=1..19.

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: A266883 A034764 A119034 * A346297 A034765 A300276

Adjacent sequences:  A100908 A100909 A100910 * A100912 A100913 A100914

KEYWORD

nonn,more

AUTHOR

Ray Chandler, Nov 21 2004

EXTENSIONS

a(1), a(14)-a(19) by Lucas A. Brown, Mar 28 2021

STATUS

approved

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Last modified December 7 19:34 EST 2021. Contains 349585 sequences. (Running on oeis4.)