A093988 Numbers k such that 2^k + 3*k is prime.
1, 3, 5, 7, 11, 13, 35, 45, 47, 57, 87, 183, 325, 367, 447, 809, 1157, 2789, 5775, 14829, 20687, 46463, 62491, 92147, 128745
Offset: 1
Programs
-
Maple
A093988:=n->`if`(isprime(2^n+3*n), n, NULL): seq(A093988(n), n=1..10^3); # Wesley Ivan Hurt, Jan 21 2017
-
Mathematica
Do[ If[ PrimeQ[2^n + 3n], Print[n]], {n, 1, 5000, 2}] -
PARI
isok(n) = isprime(2^n + 3*n); \\ Michel Marcus, Jan 21 2017
-
PFGW
ABC2 2^$a+3*$a a: from 1 to 1000 // Jinyuan Wang, Feb 03 2020
Extensions
a(19)-a(21) from Ryan Propper, Jul 05 2005
a(22)-a(23) from Michael S. Branicky, May 19 2023
a(24)-a(25) from Michael S. Branicky, Jul 24 2024
Comments