This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A235507 #23 Sep 02 2017 10:54:30
%S A235507 1,2,3,4,5,6,7,8,9,10,12,18,20,21,24,27,30,36,40,42,45,48,50,54,60,63,
%T A235507 70,72,80,81,84,90,100,108,120,162,180,200,210,216,240,243,270,300,
%U A235507 324,360,378,400,405,420,432,450,480,486,500,540,600,630,648,700,720
%N A235507 Harshad numbers which when divided by sum of their digits, give a quotient which is a Harshad number.
%C A235507 These numbers are also called MHN-2 or Multiple Harshad Numbers-2.
%H A235507 Ray Chandler, <a href="/A235507/b235507.txt">Table of n, a(n) for n = 1..10796</a> (all a(n) <= 10^6)
%H A235507 Wikipedia, <a href="http://en.wikipedia.org/wiki/Harshad_number">Harshad Number</a>
%e A235507 486 is a MHN as it is divisible by the sum of its digits i.e. 18. The quotient obtained, 27, is also divisible by the sum of its digits, i.e. 9.
%t A235507 mhnQ[n_]:=Module[{s=Total[IntegerDigits[n]]},Divisible[n,s]&&Divisible[ n/s,Total[IntegerDigits[n/s]]]]; Select[Range[800],mhnQ] (* _Harvey P. Dale_, Sep 02 2017 *)
%Y A235507 Cf. A005349, A235697.
%K A235507 nonn,base
%O A235507 1,2
%A A235507 _Mihir Mathur_, Jan 14 2014