A090050 Numbers having equal length of longest contiguous block of zeros and ones in binary expansion.

2, 5, 10, 12, 19, 21, 25, 38, 42, 44, 50, 51, 52, 56, 71, 75, 76, 77, 83, 85, 89, 100, 101, 102, 105, 108, 113, 142, 147, 150, 153, 154, 155, 166, 170, 172, 178, 179, 180, 184, 199, 201, 202, 203, 204, 205, 210, 211, 212, 217, 226, 227, 232, 240, 271, 279, 284

Offset

1,1

Comments

A087117(a(n)) = A038374(a(n)), see also A000975.

Links

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

Index entries for sequences related to binary expansion of n

Example

180 -> '10110100' with A087117(180)=2 and A038374(180)=2, therefore 180 is a term.

Mathematica

zobQ[n_]:=Module[{s=Split[IntegerDigits[n, 2]]}, Max[Length/@Select[ s, MemberQ[ #, 0]&]] == Max[Length/@Select[s, MemberQ[#, 1]&]]]; Select[ Range[ 300], zobQ] (* Harvey P. Dale, Aug 25 2019 *)
Select[Range@1000, (s=Split@IntegerDigits[#, 2]; Length@s>1 && Last@Differences@(Length@# & /@ Union@s) == 0) &] (* Hans Rudolf Widmer, Oct 10 2023 *)

Prog

(Haskell)
a090050 n = a090050_list !! (n+1)
a090050_list = [x | x <- [1..], a087117 x == a038374 x]
-- Reinhard Zumkeller, May 01 2012

Crossrefs

Cf. A031443 (binary digitally balanced).

Cf. A000975, A038374, A087117.

Sequence in context: A080792 A351062 A182656 * A274454 A192539 A046462

Adjacent sequences: A090047 A090048 A090049 * A090051 A090052 A090053

Keyword

nonn,base

Author

Reinhard Zumkeller, Nov 20 2003

Extensions

Definition corrected, thanks to Leroy Quet. - Sep 17 2008

Status

approved