A078206 - OEIS

%I #9 Mar 08 2015 19:37:29

%S 1,126,123264,12340776,1234553367,123456631959,12345677303863,

%T 1234567810050426,123456789137345679,1234567891008671105551,

%U 1234567891011073225118178,123456789101112073716778055751

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

%H Robert Gerbicz, May 09 2008, <a href="/A078206/b078206.txt">Table of n, a(n) for n = 1..17</a>

%e a(3) = 123264 = 321*384.

%o (PARI) A=B=0;e=f=0;U=1;for(n=1,17,if(n==U,U*=10;f++);A=U*A+n;B+=n*10^e;e+=f; T=1;C=A;while((-C)%B>=T,T*=10;C*=10);print1(C+(-C)%B",")) \\ _Robert Gerbicz_, May 09 2008

%Y Cf. A078207.

%K base,nonn

%O 1,2

%A _Amarnath Murthy_, Nov 22 2002

%E More terms from _Robert Gerbicz_, May 09 2008