A024906 - OEIS

%I #24 Sep 08 2022 08:44:48

%S 2,4,8,12,14,18,20,22,30,34,42,44,48,54,58,60,64,68,70,82,84,90,92,98,

%T 102,104,110,112,118,124,128,130,142,144,158,162,170,172,174,180,184,

%U 188,194,198,200,208,222,224,228,232,238,240,242,250,252,254,260,264,274,278,280

%N Numbers k such that 9*k + 1 is prime.

%H Vincenzo Librandi, <a href="/A024906/b024906.txt">Table of n, a(n) for n = 1..1000</a>

%p select(k->isprime(9*k+1),[$1..370]); # _Muniru A Asiru_, Jul 15 2018

%t Select[Range[400],PrimeQ[9#+1]&] (* _Vladimir Joseph Stephan Orlovsky_, Feb 25 2011 *)

%o (Magma) [n: n in [1..1000] |IsPrime(9*n+1)]; // _Vincenzo Librandi_, Nov 20 2010

%o (PARI) is(n)=isprime(9*n+1) \\ _Charles R Greathouse IV_, Feb 17 2017

%Y Cf. A061237 (associated primes).

%K nonn,easy

%O 1,1

%A _Clark Kimberling_