A059075 Numbers k such that 2*7^k + 3 is prime.

0, 1, 2, 5, 11, 30, 57, 78, 91, 390, 462, 667, 1214, 1811, 2054, 2937, 3055, 8518, 10665

Offset

1,3

Comments

a(20) > 21059. - Jinyuan Wang, Dec 08 2019

Links

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

Mathematica

Do[ If[ PrimeQ[ 2*7^n + 3 ], Print[n] ], {n, 1, 6000} ]

Prog

(PARI) is(n)=ispseudoprime(2*7^n+3) \\ Charles R Greathouse IV, Jun 13 2017

Crossrefs

Sequence in context: A264771 A176637 A272675 * A345882 A121134 A144959

Adjacent sequences: A059072 A059073 A059074 * A059076 A059077 A059078

Keyword

nonn,more

Author

Robert G. Wilson v, Feb 12 2001

Extensions

a(18)-a(19) from Jinyuan Wang, Dec 08 2019

Status

approved