

A235507


Harshad numbers which when divided by sum of their digits, give a quotient which is a Harshad number.


5



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, 70, 72, 80, 81, 84, 90, 100, 108, 120, 162, 180, 200, 210, 216, 240, 243, 270, 300, 324, 360, 378, 400, 405, 420, 432, 450, 480, 486, 500, 540, 600, 630, 648, 700, 720
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OFFSET

1,2


COMMENTS

These numbers are also called MHN2 or Multiple Harshad Numbers2.


LINKS

Ray Chandler, Table of n, a(n) for n = 1..10796 (all a(n) <= 10^6)
Wikipedia, Harshad Number


EXAMPLE

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.


MATHEMATICA

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 *)


CROSSREFS

Cf. A005349, A235697.
Sequence in context: A285829 A225780 A225782 * A235697 A085135 A085133
Adjacent sequences: A235504 A235505 A235506 * A235508 A235509 A235510


KEYWORD

nonn,base


AUTHOR

Mihir Mathur, Jan 14 2014


STATUS

approved



