Primes p such that p, p+6, p+12, p+18 are all primes.

Terms

a(0) =5a(1) =11a(2) =41a(3) =61a(4) =251a(5) =601a(6) =641a(7) =1091a(8) =1481a(9) =1601a(10) =1741a(11) =1861a(12) =2371a(13) =2671a(14) =3301a(15) =3911a(16) =4001a(17) =5101a(18) =5381a(19) =5431a(20) =5641a(21) =6311a(22) =6361a(23) =9461a(24) =11821a(25) =12101a(26) =12641a(27) =13451a(28) =14621a(29) =14741