a(1) = 1, then product of consecutive composite numbers sandwiched between primes.

Terms

a(0) =1a(1) =2a(2) =1a(3) =3a(4) =4a(5) =5a(6) =6a(7) =7a(8) =720a(9) =11a(10) =12a(11) =13a(12) =3360a(13) =17a(14) =18a(15) =19a(16) =9240a(17) =23a(18) =11793600a(19) =29a(20) =30a(21) =31a(22) =45239040a(23) =37a(24) =59280a(25) =41a(26) =42a(27) =43a(28) =91080a(29) =47