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Positive numbers such that the digital sum base 2 and the digital sum base 10 are in a ratio of 2:10.
12

%I #21 May 25 2024 21:40:56

%S 32,69,136,168,276,389,514,546,596,640,672,785,848,1284,1289,1298,

%T 1793,1798,1856,1888,2058,2080,2184,2369,2562,2594,2698,2896,3089,

%U 3589,4164,4169,4178,4196,4353,4358,4376,4385,4416,4448,4484,4489,4498,4628,4673

%N Positive numbers such that the digital sum base 2 and the digital sum base 10 are in a ratio of 2:10.

%C Subsequence of A227793. - _Michel Marcus_, Sep 23 2013

%H Harvey P. Dale, <a href="/A135110/b135110.txt">Table of n, a(n) for n = 1..1000</a>

%e a(1)=32, since ds_2(32):ds_10(32)=1:5=2:10.

%t Select[Range[5000],5*Total[IntegerDigits[#,2]]==Total[ IntegerDigits[ #]]&] (* _Harvey P. Dale_, Sep 14 2012 *)

%o (PARI) is(n)=sumdigits(n)/hammingweight(n)==5 \\ _Charles R Greathouse IV_, Sep 22 2013

%Y Cf. A007953, A227793.

%K nonn,base

%O 1,1

%A _Hieronymus Fischer_, Dec 24 2007