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Niven (or Harshad) numbers A005349 divided by the sum of their digits.
11

%I #22 May 26 2024 08:30:11

%S 1,1,1,1,1,1,1,1,1,10,4,2,10,7,4,3,10,4,10,7,5,4,10,6,10,7,10,8,10,9,

%T 7,10,100,34,12,55,37,28,19,13,40,14,22,19,15,28,16,25,19,17,13,18,19,

%U 20,19,16,13,11,100,67,34,23,19,70,24,55,37,28,25,19,46,26,40,27,19,28,29

%N Niven (or Harshad) numbers A005349 divided by the sum of their digits.

%C a(n)=10234 is particularly frequent, it is obtained by the following integers: 102340, 133042, 153510, 184212, 204680, 214914, 225148, 235382, 245616, 255850, 266084, 276318, 286552, 327488, 347956, 378658, 388892,.... _Carmine Suriano_, May 04 2013

%H Carmine Suriano, <a href="/A113315/b113315.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A005349(n)/A007953(A005349(n)). - _Michel Marcus_, Oct 09 2013

%e 12 is the 11th term of A005349, hence a(11) = 12/(1+2) = 4.

%t Select[# / DigitSum[#] & /@ Range[300], IntegerQ] (* _Amiram Eldar_, May 26 2024 *)

%o (PARI) lista(nn) = {for (i = 1, nn, if (i % sumdigits(i) == 0, print1(i/sumdigits(i), ", ")););} \\ _Michel Marcus_, Oct 09 2013

%Y Cf. A005349 (Niven (or Harshad) numbers: numbers that are divisible by the sum of their digits). Cf. also A066355.

%K nonn,base

%O 1,10

%A _Amarnath Murthy_, Dec 20 2001

%E Corrected, extended and edited by _Zak Seidov_, Oct 26 2005