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A177869 Integers divisible by their number of digits in binary. 2
1, 2, 6, 8, 12, 20, 25, 30, 36, 42, 48, 54, 60, 70, 77, 84, 91, 98, 105, 112, 119, 126, 128, 136, 144, 152, 160, 168, 176, 184, 192, 200, 208, 216, 224, 232, 240, 248, 261, 270, 279, 288, 297, 306, 315, 324, 333, 342, 351, 360, 369, 378, 387, 396, 405 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Daniel Arribas, Table of n, a(n) for n = 1..1000

EXAMPLE

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

MATHEMATICA

Select[Range[410], IntegerQ[#/Length[IntegerDigits[#, 2]]] &] (* Alonso del Arte, Dec 13 2010 *)

PROG

(Python) import math

for n in xrange(1, 1000):

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

(Haskell)

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

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

bin_interesting g = interesting 2 g

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

cnst = weights [1, 1]

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

(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

CROSSREFS

Base 10 equivalent is A098952.

Sequence in context: A162860 A093006 A280236 * A138639 A082473 A325177

Adjacent sequences:  A177866 A177867 A177868 * A177870 A177871 A177872

KEYWORD

nonn,base

AUTHOR

Grant Garcia, Dec 13 2010

STATUS

approved

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Last modified November 15 19:18 EST 2019. Contains 329149 sequences. (Running on oeis4.)