login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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. 1

%I #5 Jan 18 2013 08:27:03

%S 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 6,129,100012,0

%N 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 a(29), 2n-1 = 57, is at least 1e8.

%Y Cf. A077189.

%K base,nonn

%O 1,2

%A _Franklin T. Adams-Watters_, Jun 02 2006

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 19 18:05 EDT 2024. Contains 371798 sequences. (Running on oeis4.)