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 A177869 Integers divisible by their number of digits in binary. 2

%I

%S 1,2,6,8,12,20,25,30,36,42,48,54,60,70,77,84,91,98,105,112,119,126,

%T 128,136,144,152,160,168,176,184,192,200,208,216,224,232,240,248,261,

%U 270,279,288,297,306,315,324,333,342,351,360,369,378,387,396,405

%N Integers divisible by their number of digits in binary.

%H Daniel Arribas, <a href="/A177869/b177869.txt">Table of n, a(n) for n = 1..1000</a>

%e 105 is 1101001 in base 2 (length of 7); 105 / 7 is 15.

%t Select[Range[410], IntegerQ[#/Length[IntegerDigits[#, 2]]] &] (* _Alonso del Arte_, Dec 13 2010 *)

%o (Python) import math

%o for n in range(1, 1000):

%o .if not n % int(math.log(n, 2) + 1): print n # Garcia

%o base_weight b g n | n == 0 = 0 | otherwise = (base_weight b g (n `div` b)) + (g \$ n `mod` b)

%o interesting b g = filter f [1..] where f n = n `mod` (base_weight b g n) == 0

%o bin_interesting g = interesting 2 g

%o weights l n | (n >=0) && ((length l) > fromInteger n) = l !! fromInteger n | otherwise = 0

%o cnst = weights [1, 1]

%o let sequence = bin_interesting cnst -- Victor S. Miller, Oct 17 2011

%o (PARI) for(d=1, 9, forstep(n=(2^(d-1)+d-1)\d*d, 2^d-1, d, print1(n", "))) \\ _Charles R Greathouse IV_, Oct 17 2011

%Y Base 10 equivalent is A098952.

%K nonn,base,changed

%O 1,2

%A _Grant Garcia_, Dec 13 2010

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Last modified December 9 00:32 EST 2019. Contains 329871 sequences. (Running on oeis4.)