A072860 Highest power of 3 dividing the period length of 1/prime(n) = A002371(n).

0, 1, 0, 3, 1, 3, 1, 9, 1, 1, 3, 3, 1, 3, 1, 1, 1, 3, 3, 1, 1, 1, 1, 1, 3, 1, 1, 1, 27, 1, 3, 1, 1, 1, 1, 3, 3, 81, 1, 1, 1, 9, 1, 3, 1, 9, 3, 3, 1, 3, 1, 1, 3, 1, 1, 1, 1, 1, 3, 1, 3, 1, 9, 1, 3, 1, 1, 3, 1, 1, 1, 1, 3, 3, 27, 1, 1, 9, 1, 3, 1, 1, 1, 27, 3, 1, 1, 1, 1, 1, 1, 1, 243, 1, 3, 1, 1, 1, 9, 27

Offset: 1

Author

Benoit Cloitre, Jul 26 2002

Keywords

• base
• easy
• nonn

Crossrefs

Cf. A002371.

Programs

PARI

for n>3 ? a(n)=if(n<4,n==2,znorder(Mod(10, prime(n)))) ? for(n=4,150,print1(gcd(a(n),3^100),","))