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A215020 a(n) = log_2( A182105(n) ).

%I A215020 #30 Sep 27 2019 13:23:36
%S A215020 0,0,1,0,0,1,2,0,0,1,0,0,1,2,3,0,0,1,0,0,1,2,0,0,1,0,0,1,2,3,4,0,0,1,
%T A215020 0,0,1,2,0,0,1,0,0,1,2,3,0,0,1,0,0,1,2,0,0,1,0,0,1,2,3,4,5,0,0,1,0,0,
%U A215020 1,2,0,0,1,0,0,1,2,3,0,0,1,0,0,1,2,0,0,1,0,0,1,2,3,4,0,0,1,0,0,1,2,0,0,1,0,0,1,2,3,0,0,1,0,0,1,2,0,0,1
%N A215020 a(n) = log_2( A182105(n) ).
%C A215020 Apparently the leftmost positions of change with incrementing skew-binary numbers (A169683), see example. - _Joerg Arndt_, May 27 2016
%C A215020 Irregular table read by rows, where the k-th row counts from 0 up to the ruler function of k, A007814(k). - _Allan C. Wechsler_, Sep 26 2019
%H A215020 Wikipedia, <a href="https://en.wikipedia.org/wiki/Skew_binary_number_system">Skew binary number system</a>
%F A215020 a(n) = A082850(n) - 1. - _Omar E. Pol_, Jun 18 2019
%e A215020 From _Joerg Arndt_, May 27 2016: (Start)
%e A215020 The first nonnegative skew-binary numbers (dots denote zeros) are
%e A215020 n :  [skew-binary]  position of change
%e A215020 00:  [ . . . . . ]  -
%e A215020 01:  [ . . . . 1 ]  0
%e A215020 02:  [ . . . . 2 ]  0
%e A215020 03:  [ . . . 1 . ]  1
%e A215020 04:  [ . . . 1 1 ]  0
%e A215020 05:  [ . . . 1 2 ]  0
%e A215020 06:  [ . . . 2 . ]  1
%e A215020 07:  [ . . 1 . . ]  2
%e A215020 08:  [ . . 1 . 1 ]  0
%e A215020 09:  [ . . 1 . 2 ]  0
%e A215020 10:  [ . . 1 1 . ]  1
%e A215020 11:  [ . . 1 1 1 ]  0
%e A215020 12:  [ . . 1 1 2 ]  0
%e A215020 13:  [ . . 1 2 . ]  1
%e A215020 14:  [ . . 2 . . ]  2
%e A215020 15:  [ . 1 . . . ]  3
%e A215020 16:  [ . 1 . . 1 ]  0
%e A215020 17:  [ . 1 . . 2 ]  0
%e A215020 18:  [ . 1 . 1 . ]  1
%e A215020 19:  [ . 1 . 1 1 ]  0
%e A215020 20:  [ . 1 . 1 2 ]  0
%e A215020 21:  [ . 1 . 2 . ]  1
%e A215020 22:  [ . 1 1 . . ]  2
%e A215020 23:  [ . 1 1 . 1 ]  0
%e A215020 24:  [ . 1 1 . 2 ]  0
%e A215020 25:  [ . 1 1 1 . ]  1
%e A215020 26:  [ . 1 1 1 1 ]  0
%e A215020 27:  [ . 1 1 1 2 ]  0
%e A215020 28:  [ . 1 1 2 . ]  1
%e A215020 29:  [ . 1 2 . . ]  2
%e A215020 30:  [ . 2 . . . ]  3
%e A215020 31:  [ 1 . . . . ]  4
%e A215020 32:  [ 1 . . . 1 ]  0
%e A215020 33:  [ 1 . . . 2 ]  0
%e A215020 ...
%e A215020 (End)
%e A215020 From _Allan C. Wechsler_, Sep 27 2019 (Start)
%e A215020 First few rows of irregular table derived from A007814 (see comments).
%e A215020 0
%e A215020 0 1
%e A215020 0
%e A215020 0 1 2
%e A215020 0
%e A215020 0 1
%e A215020 0
%e A215020 0 1 2 3
%e A215020 0
%e A215020 0 1
%e A215020 ...
%e A215020 (End)
%Y A215020 Cf. A182105, A082850, A007814.
%K A215020 nonn
%O A215020 1,7
%A A215020 _N. J. A. Sloane_, Aug 01 2012