A342302 - OEIS

%I #28 Apr 05 2021 03:58:00

%S 6,12,48,90,252,294,300,420,432,720,798,864,930,1020,1140,1218,1368,

%T 1428,1602,1716,1890,1938,2088,2184,2190,2196,2250,2760,2880,3588,

%U 3660,3708,3774,3810,4452,4710,4902,5280,5340,5412,5754,5850,6174,6240,6462,6768,7014,7182,7632,8322,8820,9144

%N Numbers k such that A001414(k), k+A001414(k) and 2*k+A001414(k) are prime.

%C Numbers k such that A343016(k) >= 3.

%C All terms are divisible by 6.

%H Robert Israel, <a href="/A342302/b342302.txt">Table of n, a(n) for n = 1..10000</a>

%e a(3) = 48 = 2^4*3 is a term because A001414(48) = 4*2+3 = 11 and 11, 48+11 = 59 and 2*48+11 = 107 are prime.

%p filter:= proc(n) local s,t;

%p s:= add(t[1]*t[2], t=ifactors(n)[2]);

%p isprime(s) and isprime(n+s) and isprime(2*n+s)

%p end proc;

%p select(filter, [seq(i,i=6..10000,6)]);

%Y Cf. A001414, A343016.

%K nonn

%O 1,1

%A _J. M. Bergot_ and _Robert Israel_, Apr 02 2021