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%I #5 Nov 21 2013 12:49:20
%S 1,2,6,3,5,12,4,5,45,9,8,17,5,5,13,4,4,25,1,0,4,0,0,1,0,0,1
%N The number of 3-digit multiples of n whose digits sum to n.
%e a(1)=1 as 100 is the only 3-digit multiple of 1 whose digits sum to 1, while a(19)=1 as 874 is the only 3-digit multiple of 19 with the property.
%t dm3[n_]:=Module[{min=n*Ceiling[100/n],max=n*Floor[999/n]},Length[ Select[Range[min,max,n],Total[IntegerDigits[#]]==n&]]]; Array[dm3,30] (* _Harvey P. Dale_, Dec 18 2011 *)
%K base,full,nonn,fini
%O 1,2
%A _Ian Duff_, Jun 08 2008