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A209064 Numbers n whose divisors, when expressed in binary, have lengths 1 to tau(n). 1
1, 2, 3, 4, 8, 10, 14, 15, 16, 32, 44, 50, 52, 63, 64, 128, 136, 152, 170, 184, 190, 230, 231, 232, 238, 248, 250, 255, 256, 484, 512, 592, 656, 688, 752, 848, 944, 976, 1024, 2048, 2144, 2272, 2312, 2336, 2528, 2656, 2848, 2888, 2890, 2948, 3104, 3124, 3212 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Subsequence of A135772 (numbers having equal number of divisors and binary digits).

Supersequence of A000079 (powers of 2).

LINKS

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

EXAMPLE

Divisors of n in base 2 (k-th divisor contains k digits):

n=1:   1;

n=16:  1, 10, 100, 1000, 10000;

n=230: 1, 10, 101, 1010, 10111, 101110, 1110011, 11100110.

MATHEMATICA

Join[{1}, Select[Range[4000], Union[Differences[Length /@ IntegerDigits[Divisors[#], 2]]] == {1} &]] (* T. D. Noe, Mar 12 2012 *)

CROSSREFS

Cf. A135772.

Sequence in context: A180941 A190896 A135772 * A222264 A051783 A033083

Adjacent sequences:  A209061 A209062 A209063 * A209065 A209066 A209067

KEYWORD

nonn,base

AUTHOR

Jaroslav Krizek, Mar 04 2012

STATUS

approved

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Last modified January 22 16:47 EST 2019. Contains 319364 sequences. (Running on oeis4.)