A175174 Least primitive number k such that 1/k is in the Cantor set and the fraction 1/k has period n in base 3.

1, 4, 13, 10, 121, 28, 1093, 82, 757, 244, 88573, 730, 797161, 2188, 59293, 6562, 64570081, 1036, 581130733, 2362, 4785157, 177148, 47071589413, 84253, 3501192601, 1594324, 387440173, 4782970, 34315188682441, 66124

Offset: 1

Author

T. D. Noe, Feb 28 2010

Keywords

• nonn

Comments

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.

Links

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