a(n) = sum of exponents in prime-power factorization of prime(n) + 1.

Terms

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