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A072081 Numbers divisible by the square of the sum of their digits in base 10. 9

%I

%S 1,10,20,50,81,100,112,162,200,243,324,392,400,405,500,512,605,648,

%T 810,972,1000,1053,1100,1120,1134,1183,1215,1296,1400,1620,1701,1900,

%U 1944,2000,2025,2106,2156,2240,2268,2300,2401,2430,2511,2592,2704,2800,2916

%N Numbers divisible by the square of the sum of their digits in base 10.

%H Donovan Johnson, <a href="/A072081/b072081.txt">Table of n, a(n) for n = 1..1000</a>

%e n=9477, sumdigit(9477)=27, q=9477=27.27.13.

%t sud[x_] := Apply[Plus, IntegerDigits[x]] Do[s=sud[n]^2; If[IntegerQ[n/s], Print[n]], {n, 1, 10000}]

%t Select[Range[3000],Divisible[#,Total[IntegerDigits[#]]^2]&] (* _Harvey P. Dale_, May 04 2011 *)

%o (PARI) for(n=1,10^4,s=sumdigits(n);if(!(n%s^2),print1(n,", "))) \\ _Derek Orr_, Apr 29 2015

%Y Cf. A005349, A003634.

%K base,nonn,easy

%O 1,2

%A _Labos Elemer_, Jun 14 2002

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Last modified November 13 15:41 EST 2019. Contains 329106 sequences. (Running on oeis4.)