Numbers n such that n!3 + 3 is prime, where n!3 = n!!! is a triple factorial number (A007661).

Terms

a(0) =2a(1) =4a(2) =5a(3) =7a(4) =8a(5) =10a(6) =11a(7) =13a(8) =14a(9) =16a(10) =19a(11) =20a(12) =26a(13) =28a(14) =29a(15) =32a(16) =41a(17) =56a(18) =61a(19) =77a(20) =100a(21) =169a(22) =181a(23) =205a(24) =338a(25) =347a(26) =955a(27) =1952a(28) =2197a(29) =2428