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A059454 Numbers k such that 2*3^k - 7 is prime. 3
2, 3, 5, 6, 9, 14, 39, 51, 73, 101, 155, 183, 286, 291, 310, 313, 335, 570, 951, 1011, 1183, 1930, 2586, 3423, 6486, 7791, 11586, 14290, 18590, 29595 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(31) > 30359. - Jinyuan Wang, Jan 20 2020

LINKS

Table of n, a(n) for n=1..30.

MATHEMATICA

Do[ If[ PrimeQ[ 2*3^n - 7 ], Print[n] ], {n, 1, 5700} ]

PROG

(PARI) is(n)=ispseudoprime(2*3^n-7) \\ Charles R Greathouse IV, May 22 2017

(MAGMA) [n: n in [1..1000] | IsPrime(2*3^n-7)]; // Jinyuan Wang, Jan 20 2020

CROSSREFS

Cf. A059326 (2*3^k + 7 is prime).

Sequence in context: A295631 A278707 A294631 * A138538 A240555 A102694

Adjacent sequences:  A059451 A059452 A059453 * A059455 A059456 A059457

KEYWORD

nonn,more

AUTHOR

Robert G. Wilson v, Feb 15 2001

EXTENSIONS

First term 0 removed by Georg Fischer, Aug 01 2019

a(27)-a(30) from Jinyuan Wang, Jan 20 2020

STATUS

approved

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Last modified September 20 19:01 EDT 2020. Contains 337265 sequences. (Running on oeis4.)