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A057913 Numbers k such that 3*2^k + 5 is prime. 2
1, 2, 3, 4, 5, 6, 7, 8, 14, 16, 19, 22, 24, 27, 29, 32, 38, 54, 57, 60, 76, 94, 132, 139, 175, 187, 208, 230, 379, 384, 632, 1040, 1188, 1359, 1553, 1734, 1768, 1925, 2492, 3272, 3537, 3949, 4647, 5869, 6473, 7036, 8550, 9459, 9784, 15440, 15507, 15637, 16400, 42045 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..54.

MATHEMATICA

Do[ If[ PrimeQ[ 3*2^n + 5 ], Print[ n ] ], {n, 1, 3000} ]

PROG

(PARI) {for(n=0, 10^6, if(isprime(k=5+3*2^n), print1(n, ", ")))} /* Joerg Arndt, Apr 13 2012 */

CROSSREFS

Cf. A057912 (3*2^k + 5 is prime).

Sequence in context: A032904 A208530 A088416 * A245802 A085904 A032997

Adjacent sequences:  A057910 A057911 A057912 * A057914 A057915 A057916

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Nov 16 2000

EXTENSIONS

a(54) from Jinyuan Wang, Feb 02 2020

STATUS

approved

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Last modified May 9 19:00 EDT 2021. Contains 343744 sequences. (Running on oeis4.)