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Harshad numbers which when divided by their digital sum, give a quotient which is a Multiple Harshad Numbers-2.
3

%I #12 Jun 13 2024 05:35:04

%S 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 70,72,80,81,84,90,100,108,120,162,180,200,210,216,240,243,270,300,

%U 324,360,378,400,405,420,432,450,480,486,500,540,600,630,648,700,720,756,800,810,840,864,900,972,1000,1080,1200,1296,1458

%N Harshad numbers which when divided by their digital sum, give a quotient which is a Multiple Harshad Numbers-2.

%C These numbers are also called MHN-3 or Multiple Harshad Numbers-3.

%C A Multiple Harshad number is a Harshad number that, when divided by the sum of its digits, produces another Harshad number.

%C Starts to differ from A235507 at position n=70. - _R. J. Mathar_, Jun 13 2024

%H Ray Chandler, <a href="/A235697/b235697.txt">Table of n, a(n) for n = 1..1947</a> (all a(n) <= 10^6)

%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Harshad_number">Harshad Number</a>

%e 756 is a term as it gives quotient 42 on division by the digital sum (i.e. 18). 42 gives quotient 7 on division by its digital sum (i.e. 6). As 7 is also a Harshad Number, thus 756 is a MHN-3.

%Y Cf. A005349, A235507.

%K nonn,base

%O 1,2

%A _Mihir Mathur_, Jan 14 2014