A038585 Write n in binary, delete 0's.

1, 1, 11, 1, 11, 11, 111, 1, 11, 11, 111, 11, 111, 111, 1111, 1, 11, 11, 111, 11, 111, 111, 1111, 11, 111, 111, 1111, 111, 1111, 1111, 11111, 1, 11, 11, 111, 11, 111, 111, 1111, 11, 111, 111, 1111, 111, 1111, 1111, 11111, 11, 111, 111, 1111, 111, 1111, 1111

Offset

1,3

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Index entries for sequences related to binary expansion of n

Formula

a(n) = (9 * n mod 2 + 1) * a(floor(n/2)) + n mod 2. - Reinhard Zumkeller, Oct 10 2012

a(n) = A002275(A000120(n)). - Chai Wah Wu, May 19 2020

Mathematica

Table[FromDigits[DeleteCases[IntegerDigits[n, 2], _?(#==0&)]], {n, 60}] (* Harvey P. Dale, Feb 27 2012 *)
FromDigits/@(IntegerDigits[Range[60], 2]/.(0->Nothing)) (* Harvey P. Dale, Apr 09 2017 *)

Prog

(Haskell)
a038585 0 = 0
a038585 n = (9 * m + 1) * (a038585 n') + m where (n', m) = divMod n 2
-- Reinhard Zumkeller, Oct 10 2012
(Python)
def A038585(n):
    return int(bin(n)[2:].replace('0', '')) # Chai Wah Wu, May 19 2020

Crossrefs

Cf. A000120, A002275, A038573.

Sequence in context: A281036 A205321 A270838 * A083768 A279695 A282219

Adjacent sequences: A038582 A038583 A038584 * A038586 A038587 A038588

Keyword

nonn,easy,base,nice

Author

N. J. A. Sloane

Extensions

More terms from Erich Friedman

Status

approved