A221714 Numbers written in base 2 with digits rearranged to be in decreasing order.

0, 1, 10, 11, 100, 110, 110, 111, 1000, 1100, 1100, 1110, 1100, 1110, 1110, 1111, 10000, 11000, 11000, 11100, 11000, 11100, 11100, 11110, 11000, 11100, 11100, 11110, 11100, 11110, 11110, 11111, 100000, 110000, 110000, 111000, 110000

Offset

0,3

Comments

This is the base-2 equivalent of A004186.

Links

Indranil Ghosh, Table of n, a(n) for n = 0..10000

Mathematica

a[n_] := FromDigits[-Sort[-IntegerDigits[n, 2]]] (* Giovanni Resta, Jan 27 2013 *)

Prog

(Python)
def a(n):
     return "".join(sorted(bin(n)[2:], reverse=True)) # Indranil Ghosh, Jan 09 2017

Crossrefs

For decimal equivalents see A073138.

Cf. A004086, A004185, A004186, A009996.

Sequence in context: A234472 A139707 A139709 * A309761 A108779 A288336

Adjacent sequences: A221711 A221712 A221713 * A221715 A221716 A221717

Keyword

nonn,base,easy

Author

Bruce L. Rothschild and N. J. A. Sloane, Jan 26 2013

Extensions

a(18)-a(36) from Giovanni Resta, Jan 27 2013

Status

approved