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A072602
Numbers such that in base 2 the number of 0's is >= the number of 1's.
8
2, 4, 8, 9, 10, 12, 16, 17, 18, 20, 24, 32, 33, 34, 35, 36, 37, 38, 40, 41, 42, 44, 48, 49, 50, 52, 56, 64, 65, 66, 67, 68, 69, 70, 72, 73, 74, 76, 80, 81, 82, 84, 88, 96, 97, 98, 100, 104, 112, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142
OFFSET
1,1
LINKS
T. D. Noe, Table of n, a(n) for n = 1..7555 (numbers up to 2^14)
Jason Bell, Thomas Finn Lidbetter, Jeffrey Shallit, Additive Number Theory via Approximation by Regular Languages, arXiv:1804.07996 [cs.FL], 2018.
Thomas Finn Lidbetter, Counting, Adding, and Regular Languages, Master's Thesis, University of Waterloo, Ontario, Canada, 2018.
EXAMPLE
8 is present because '1000' contains 3 '0's and 1 '1': 3 >= 1;
9 is present because '1001' contains 2 '0's and 2 '1's: 2 >= 2.
MATHEMATICA
Select[Range[150], DigitCount[#, 2, 0]>=DigitCount[#, 2, 1]&] (* Harvey P. Dale, May 09 2012 *)
PROG
(Haskell)
a072602 n = a072602_list !! (n-1)
a072602_list = filter ((>= 0) . a037861) [1..]
-- Reinhard Zumkeller, Mar 31 2015
(PARI) is(n)=2*hammingweight(n)<=exponent(n)+1 \\ Charles R Greathouse IV, Apr 18 2020
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Reinhard Zumkeller, Jun 23 2002
EXTENSIONS
Edited by N. J. A. Sloane, Jun 23 2009
STATUS
approved