%I #16 Aug 03 2014 14:01:39
%S 1,2,3,4,8,10,14,15,16,32,44,50,52,63,64,128,136,152,170,184,190,230,
%T 231,232,238,248,250,255,256,484,512,592,656,688,752,848,944,976,1024,
%U 2048,2144,2272,2312,2336,2528,2656,2848,2888,2890,2948,3104,3124,3212
%N Numbers n whose divisors, when expressed in binary, have lengths 1 to tau(n).
%C Subsequence of A135772 (numbers having equal number of divisors and binary digits).
%C Supersequence of A000079 (powers of 2).
%H Vincenzo Librandi, <a href="/A209064/b209064.txt">Table of n, a(n) for n = 1..1000</a>
%e Divisors of n in base 2 (k-th divisor contains k digits):
%e n=1: 1;
%e n=16: 1, 10, 100, 1000, 10000;
%e n=230: 1, 10, 101, 1010, 10111, 101110, 1110011, 11100110.
%t Join[{1}, Select[Range[4000], Union[Differences[Length /@ IntegerDigits[Divisors[#], 2]]] == {1} &]] (* _T. D. Noe_, Mar 12 2012 *)
%Y Cf. A135772.
%K nonn,base
%O 1,2
%A _Jaroslav Krizek_, Mar 04 2012
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