A192190 Degree of A192189(n) (polynomial-like numbers) in term of number derivatives: number of A003415-iterations up to reaching 0.

0, 1, 1, 1, 2, 1, 3, 2, 1, 1, 4, 1, 1, 3, 2, 1, 3, 1, 1, 5, 2, 1, 4, 1, 2, 1, 4, 1, 5, 1, 3, 2, 1, 1, 6, 2, 1, 2, 1, 1, 2, 1, 2, 1, 3, 1, 3, 6, 1, 1, 1, 2, 1, 1, 1, 2, 2, 3, 1, 5, 2, 1, 1, 4, 1, 2, 3, 1, 1, 2, 1, 1, 2, 4, 1, 6, 1, 2, 7, 1, 1, 2, 3, 1, 1, 1, 1, 3, 2, 5, 3, 1, 2, 5, 2

Offset: 1

Author

Vladimir Shevelev, Jun 25 2011

Keywords

• nonn

Comments

a(n) = 1 iff A192189(n) is prime.

Crossrefs

Cf. A003415, A038554, A192082, A192189.