Number of distinct prime divisors of prime(n)*prime(n-1) + 1.

Terms

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