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Numbers divisible by the sum of k times the k-th digit.
1

%I #9 Feb 08 2021 02:56:16

%S 1,2,3,4,5,6,7,8,9,10,19,20,30,38,40,50,57,60,70,76,80,90,95,100,104,

%T 120,190,200,207,208,231,240,252,300,310,360,380,400,403,414,430,432,

%U 462,465,480,500,506,528,570,600,620,625,629,693,700,702,714,754,760,800,805,806

%N Numbers divisible by the sum of k times the k-th digit.

%H Amiram Eldar, <a href="/A117241/b117241.txt">Table of n, a(n) for n = 1..10000</a>

%e 95 is in the sequence because 1*9 + 2*5 = 19 and 95 is divisible by 19.

%e 1232 is in the sequence because 1*1 + 2*2 + 3*3 + 4*2 = 22 and 1232 is divisible by 22.

%t Select[Range[1000], Divisible[#, Plus @@ ((d = IntegerDigits[#]) * Range[Length[d]])] &] (* _Amiram Eldar_, Feb 08 2021 *)

%Y Cf. A156207.

%K base,nonn

%O 1,2

%A Luc Stevens (lms022(AT)yahoo.com), Apr 22 2006

%E Missing terms inserted by _Amiram Eldar_, Feb 08 2021