A120008 - cp's OEIS frontend

A120008 Smallest k such that the concatenation from 1 to k and back to 1 is divisible by 2n-1, or 0 if no such k exists.

%I A120008 #5 Jan 18 2013 08:27:03
%S A120008 1,3,0,6,3,2,6,0,109,103,6,100001,0,9,1006,17,6,0,3,6,5,103,0,1000002,
%T A120008 6,129,100012,0
%N A120008 Smallest k such that the concatenation from 1 to k and back to 1 is divisible by 2n-1, or 0 if no such k exists.
%C A120008 a(29), 2n-1 = 57, is at least 1e8.
%Y A120008 Cf. A077189.
%K A120008 base,nonn
%O A120008 1,2
%A A120008 _Franklin T. Adams-Watters_, Jun 02 2006

cp's OEIS Frontend

A120008 Smallest k such that the concatenation from 1 to k and back to 1 is divisible by 2n-1, or 0 if no such k exists.