a(n) = sum of distinct prime divisors of prime(n) - 1.

Terms

a(0) =0a(1) =2a(2) =2a(3) =5a(4) =7a(5) =5a(6) =2a(7) =5a(8) =13a(9) =9a(10) =10a(11) =5a(12) =7a(13) =12a(14) =25a(15) =15a(16) =31a(17) =10a(18) =16a(19) =14a(20) =5a(21) =18a(22) =43a(23) =13a(24) =5a(25) =7a(26) =22a(27) =55a(28) =5a(29) =9