To get next term, multiply by 17, add 1 and discard any prime factors < 17.

Terms

a(0) =61a(1) =173a(2) =1471a(3) =521a(4) =4429a(5) =4183a(6) =2963a(7) =257a(8) =437a(9) =743a(10) =1579a(11) =2237a(12) =3803a(13) =2309a(14) =19627a(15) =5561a(16) =47269a(17) =14881a(18) =3833a(19) =32581a(20) =263a(21) =43a(22) =61a(23) =173a(24) =1471a(25) =521a(26) =4429a(27) =4183a(28) =2963a(29) =257