A095139 Number of distinct prime factors of A095137(n).

1, 0, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 3, 3, 3, 1, 2, 2, 2, 2, 1, 2, 3, 1, 2, 2, 3, 1, 2, 3, 2, 2, 1, 2, 2, 2, 6, 2, 1, 3, 4, 5, 2, 5, 3, 2, 3, 3, 3, 3, 2, 4, 3, 4, 5, 6, 1, 3, 2, 4, 2, 2, 4, 3, 2, 3, 6, 4, 6, 4, 3

Offset: 1

Author

Robert G. Wilson v, May 28 2004

Keywords

• nonn

Crossrefs

Cf. A095137.

Programs

Mathematica

PrimeFactors[n_] := Flatten[ Table[ #[[1]], {1} ] & /@ FactorInteger[n]]; f[n_] := Abs[ Product[ Prime[i], {i, 2, n, 2}] + Product[ Prime[i], {i, 1, n, 2}]]; f[1] = 2; Table[ Length[ PrimeFactors[ f[n]]], {n, 72}]