Becomes prime or 4 after exactly 8 iterations of f(x) = sum of prime factors of x.

Terms

a(0) =1257a(1) =1556a(2) =1774a(3) =1982a(4) =2566a(5) =2649a(6) =4249a(7) =4405a(8) =4497a(9) =4645a(10) =5086a(11) =5169a(12) =5286a(13) =5317a(14) =5462a(15) =5574a(16) =6070a(17) =6074a(18) =6382a(19) =6518a(20) =7064a(21) =7149a(22) =7197a(23) =7284a(24) =7694a(25) =7813a(26) =7947a(27) =8043a(28) =8193a(29) =8593