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!)
A078204 Smallest multiple of the concatenation of 1 up to n that begins with the concatenation of n down to 1. 1

%I #7 Dec 05 2013 19:55:56

%S 1,216,32103,4321468,543217035,65432173824,7654321572835,

%T 876543212074068,98765432187654312,109876543212580239340,

%U 11109876543210457373921742,12111098765432151566924849880

%N Smallest multiple of the concatenation of 1 up to n that begins with the concatenation of n down to 1.

%e a(3) = 32103 = 123 * 261.

%t f[n_] := Module[{upto = FromDigits[Range[n]], downfrom = FromDigits[Reverse[Range[n]]], i = 1}, While[upto - Mod[10^i downfrom, upto] > 10^i, i++ ]; 10^i downfrom + upto - Mod[10^i downfrom, upto]]; Table[f[n], {n, 2, 9}]

%Y Cf. A078205.

%K base,nonn

%O 1,2

%A _Amarnath Murthy_, Nov 22 2002

%E More terms from _Harvey P. Dale_, Dec 07 2002

%E More terms from _Sascha Kurz_, Jan 04 2003

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 August 11 01:05 EDT 2024. Contains 375059 sequences. (Running on oeis4.)