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Number of numbers less than n having a greater sum of digits.
5

%I #10 Jan 27 2014 17:18:45

%S 0,0,0,0,0,0,0,0,0,0,8,7,6,5,4,3,2,1,0,0,15,13,11,9,7,5,3,1,0,0,21,18,

%T 15,12,9,6,3,1,0,0,26,22,18,14,10,6,3,1,0,0,30,25,20,15,10,6,3,1,0,0,

%U 33,27,21,15,10,6,3,1,0,0,35,28,21,15,10,6,3,1,0,0,36,28,21,15,10,6,3,1,0

%N Number of numbers less than n having a greater sum of digits.

%C A138470(n) + A138471(n) + a(n) = n;

%C a(A067043(n)) = 0.

%H R. Zumkeller, <a href="/A138472/b138472.txt">Table of n, a(n) for n = 0..1500</a>

%H <a href="/index/Coi#Colombian">Index entries for Colombian or self numbers and related sequences</a>

%e a(42)=#{7,8,9,16,17,18,19,25,26,27,28,29,34,35,36,37,38,39}=18.

%t nn=90;With[{c=Table[{n,Total[IntegerDigits[n]]},{n,0,nn}]},Table[ Count[Take[c,i],_?(#[[2]]>c[[i,2]]&)],{i,nn}]] (* _Harvey P. Dale_, Sep 24 2012 *)

%Y Cf. A007953.

%K nonn,base,look

%O 0,11

%A _Reinhard Zumkeller_, Mar 19 2008