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A216995 Multiples of 11 whose digit sum is a multiple of 11.

%I A216995 #27 Jul 12 2021 04:13:32
%S A216995 209,308,407,506,605,704,803,902,2090,2299,2398,2497,2596,2695,2794,
%T A216995 2893,2992,3080,3289,3388,3487,3586,3685,3784,3883,3982,4070,4279,
%U A216995 4378,4477,4576,4675,4774,4873,4972,5060,5269,5368,5467,5566,5665,5764,5863,5962,6050
%N A216995 Multiples of 11 whose digit sum is a multiple of 11.
%C A216995 Nothing between 1000 and 2000.
%C A216995 Also, there are no a(n) from 10902 to 12198 (this interval contains 117 multiples of 11). [_Bruno Berselli_, Oct 26 2012]
%H A216995 Bruno Berselli, <a href="/A216995/b216995.txt">Table of n, a(n) for n = 1..1000</a>
%e A216995 3487 = 11*317 and 3+4+8+7 = 22 = 11*2.
%t A216995 Select[11*Range[1000], Mod[Total[IntegerDigits[#]], 11] == 0 &] (* _T. D. Noe_, Sep 24 2012 *)
%o A216995 (JavaScript)
%o A216995 function sumarray(arr) {
%o A216995 t=0;
%o A216995 for (i=0;i<arr.length;i++) t+=arr[i];
%o A216995 return t;
%o A216995 }
%o A216995 k=11;
%o A216995 for(s=1;s<1000;s++) {
%o A216995 a=new Array();
%o A216995 x=(s*k).toString();
%o A216995 for (j=0;j<x.length;j++) a[j]=Number(x.charAt(j));
%o A216995 if (sumarray(a)%k==0) document.write(s*k+",");
%o A216995 }
%o A216995 (Python)
%o A216995 def sd(n): return sum(map(int, str(n)))
%o A216995 def ok(n): return n%11 == 0 and sd(n)%11 == 0
%o A216995 print(list(filter(ok, range(1, 6051)))) # _Michael S. Branicky_, Jul 11 2021
%Y A216995 Cf. A008593 (multiples of 11), A166311 (digit sum multiple of 11).
%Y A216995 Cf. A216994, A216996, A216997, A216998, A217009.
%K A216995 nonn,base
%O A216995 1,1
%A A216995 _Jon Perry_, Sep 22 2012