Smallest prime factor in product of previous terms +1 or -1.

Terms

a(0) =2a(1) =3a(2) =5a(3) =29a(4) =11a(5) =7a(6) =13a(7) =37a(8) =17a(9) =79a(10) =23a(11) =4129a(12) =193a(13) =2593a(14) =101a(15) =19a(16) =39163a(17) =577a(18) =26431a(19) =131a(21) =103a(22) =163a(23) =179a(24) =293a(25) =127a(26) =6287a(27) =683437a(28) =31a(29) =89a(31) =113