A109847 - OEIS

%I #14 Sep 22 2015 14:56:58

%S 8,14,6,20,20,6,14,8,0,890,88,348,1118,1190,420,1328,1394,162,1520,

%T 1580,546,154,1748,600,1850,1898,216,1988,2030,690,2108,2144,66,2210,

%U 2240,252,2294,2318,780,2360,2378,798,2408,220,270,2438,2444,816,2450,2450

%N Least common multiple of n and its 9's complement.

%H Alois P. Heinz, <a href="/A109847/b109847.txt">Table of n, a(n) for n = 1..9999</a>

%e a(2)=14 because 7=9-2 and lcm(2,7)=14

%e a(9)=lcm(0,9)=0. a(10)=lcm(89,10)=890.

%p digs := proc(inp::integer) local resul,shiftinp : resul := 1 : shiftinp := iquo(inp,10) : while shiftinp > 0 do resul := resul+1 : shiftinp := iquo(shiftinp,10) : od : RETURN(resul) : end: nin := proc(inp::integer) RETURN(10^digs(inp)-1-inp) : end : for n from 1 to 40 do comp := nin(n) ; #print(n,comp,lcm(n,comp)) ; printf("%d,",lcm(n,comp)) ; od : # _R. J. Mathar_, Mar 27 2006

%p # second Maple program:

%p a:= n-> ilcm((10^length(n)-1-n), n):

%p seq(a(n), n=1..100);  # _Alois P. Heinz_, Sep 22 2015

%t Array[LCM[#,10^IntegerLength[#]-1-#]&,50] (* _Harvey P. Dale_, Apr 17 2012 *)

%Y Cf. A109848, A084021.

%K base,easy,nonn

%O 1,1

%A _Amarnath Murthy_, Jul 06 2005

%E Corrected and extended by _R. J. Mathar_, Mar 27 2006

%E More terms from _Joshua Zucker_, May 03 2006