1,2

Primitive means that 3 does not divide k. The term a(n) is the first term in row n of A173800. For n=p^k, with p prime and k>0, it appears that a(n) = Phi(n,3), the n-th cyclotomic polynomial evaluated at 3.

T. D. Noe, Table of n, a(n) for n=1..200

Sequence in context: A101181 A160249 A173800 * A136137 A287895 A050223

Adjacent sequences: A175171 A175172 A175173 * A175175 A175176 A175177

nonn

T. D. Noe, Feb 28 2010

approved