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A221714
Numbers written in base 2 with digits rearranged to be in decreasing order.
4
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
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.
Sequence in context: A376450 A139707 A139709 * A309761 A108779 A288336
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