Numbers k such that k!6 + 4 is prime, where k!6 is the sextuple factorial number (A085158 ).

Terms

a(0) =1a(1) =3a(2) =7a(3) =9a(4) =11a(5) =15a(6) =19a(7) =27a(8) =35a(9) =59a(10) =71a(11) =75a(12) =95a(13) =109a(14) =153a(15) =155a(16) =169a(17) =189a(18) =277a(19) =355a(20) =383a(21) =405a(22) =455a(23) =625a(24) =843a(25) =853a(26) =879a(27) =1389a(28) =1423a(29) =1515