A089648 Numbers whose numbers of zeros and ones in binary representation differ at most by 1.

0, 1, 2, 4, 5, 6, 9, 10, 12, 17, 18, 19, 20, 21, 22, 24, 25, 26, 28, 35, 37, 38, 41, 42, 44, 49, 50, 52, 56, 67, 69, 70, 71, 73, 74, 75, 76, 77, 78, 81, 82, 83, 84, 85, 86, 88, 89, 90, 92, 97, 98, 99, 100, 101, 102, 104, 105, 106, 108, 112, 113, 114, 116, 120, 135, 139

Offset

1,3

Comments

A031443 is a subsequence; abs(A037861(a(n))) <= 1.

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Digit Count

Index entries for sequences related to binary expansion of n

Mathematica

Select[Range[0, 7! ], Abs[DigitCount[ #, 2, 0]-DigitCount[ #, 2, 1]]<2 &] (* Vladimir Joseph Stephan Orlovsky, Feb 16 2010 *)

Prog

(Haskell)
a089648 n = a089648_list !! (n-1)
a089648_list = filter ((<= 1) . abs . a037861) [0..]
-- Reinhard Zumkeller, Mar 31 2015

Crossrefs

Cf. A023416, A000120.

Cf. A037861, union of A031443, A031444 and A031448.

Sequence in context: A125297 A194469 A143072 * A062861 A120629 A169694

Adjacent sequences: A089645 A089646 A089647 * A089649 A089650 A089651

Keyword

nonn,base

Author

Reinhard Zumkeller, Jan 02 2004

Status

approved