A106752 Numbers of prime factors of k, k defined in A117078.

0, 0, 1, 0, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 1, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1

Offset: 1

Author

Rémi Eismann, Jun 22 2007, Feb 14 2008

Keywords

• nonn

Comments

a(n) = 0 only for n = 1, 2 and 4.

Examples

			For a(1), k=0 thus a(1)=0,
For a(3), k=3 thus a(3)=1,
For a(11), k=25=5*5 thus a(11)=2.
		

Links

• Remi Eismann, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A117078, A117563, A118534, A118144, A118123.

Formula

a(n) = numbers of factors of A117078(n). A117078(n) : smallest k such that prime(n+1) = prime(n) + (prime(n) mod k), or 0 if no such k exists.