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Numbers k such that 12*k - 5, 12*k - 1, 12*k + 1, and 12*k + 5 are primes.
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%I #11 Dec 17 2019 07:41:09

%S 1,9,19,26,91,119,124,156,224,399,436,471,569,691,1141,1311,1339,1349,

%T 1449,1619,1729,1969,2009,2616,2779,2961,3001,3166,3369,3649,3689,

%U 6641,6834,7191,7401,7544,7791,7924,8426,8461,9214,9291,9429,9431,9744

%N Numbers k such that 12*k - 5, 12*k - 1, 12*k + 1, and 12*k + 5 are primes.

%H Amiram Eldar, <a href="/A174372/b174372.txt">Table of n, a(n) for n = 1..10000</a>

%e 1 is a term because 1*12-5=7, 1*12-1=11, 1*12+1=13, and 1*12+5=17 are all prime.

%t Select[Range[10^4], AllTrue[12# + {-5, -1, 1, 5}, PrimeQ] &] (* _Amiram Eldar_, Dec 17 2019 *)

%Y Cf. A124519.

%K nonn,easy

%O 1,2

%A _Juri-Stepan Gerasimov_, Mar 17 2010

%E Extended by _Charles R Greathouse IV_, Mar 18 2010