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A215020 a(n) = log_2( A182105(n) ). 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, 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, 0, 0, 1, 2, 3, 4, 5, 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, 0, 0, 1, 2, 0, 0, 1, 0, 0, 1, 2, 3, 0, 0, 1, 0, 0, 1, 2, 0, 0, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,7

COMMENTS

Apparently the leftmost positions of change with incrementing skew-binary numbers (A169683), see example. - Joerg Arndt, May 27 2016

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

LINKS

Table of n, a(n) for n=1..119.

Wikipedia, Skew binary number system

FORMULA

a(n) = A082850(n) - 1. - Omar E. Pol, Jun 18 2019

EXAMPLE

From Joerg Arndt, May 27 2016: (Start)

The first nonnegative skew-binary numbers (dots denote zeros) are

n :  [skew-binary]  position of change

00:  [ . . . . . ]  -

01:  [ . . . . 1 ]  0

02:  [ . . . . 2 ]  0

03:  [ . . . 1 . ]  1

04:  [ . . . 1 1 ]  0

05:  [ . . . 1 2 ]  0

06:  [ . . . 2 . ]  1

07:  [ . . 1 . . ]  2

08:  [ . . 1 . 1 ]  0

09:  [ . . 1 . 2 ]  0

10:  [ . . 1 1 . ]  1

11:  [ . . 1 1 1 ]  0

12:  [ . . 1 1 2 ]  0

13:  [ . . 1 2 . ]  1

14:  [ . . 2 . . ]  2

15:  [ . 1 . . . ]  3

16:  [ . 1 . . 1 ]  0

17:  [ . 1 . . 2 ]  0

18:  [ . 1 . 1 . ]  1

19:  [ . 1 . 1 1 ]  0

20:  [ . 1 . 1 2 ]  0

21:  [ . 1 . 2 . ]  1

22:  [ . 1 1 . . ]  2

23:  [ . 1 1 . 1 ]  0

24:  [ . 1 1 . 2 ]  0

25:  [ . 1 1 1 . ]  1

26:  [ . 1 1 1 1 ]  0

27:  [ . 1 1 1 2 ]  0

28:  [ . 1 1 2 . ]  1

29:  [ . 1 2 . . ]  2

30:  [ . 2 . . . ]  3

31:  [ 1 . . . . ]  4

32:  [ 1 . . . 1 ]  0

33:  [ 1 . . . 2 ]  0

...

(End)

From Allan C. Wechsler, Sep 27 2019 (Start)

First few rows of irregular table derived from A007814 (see comments).

0

0 1

0

0 1 2

0

0 1

0

0 1 2 3

0

0 1

...

(End)

CROSSREFS

Cf. A182105, A082850, A007814.

Sequence in context: A330005 A165277 A245194 * A103612 A083913 A023670

Adjacent sequences:  A215017 A215018 A215019 * A215021 A215022 A215023

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Aug 01 2012

STATUS

approved

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Last modified June 24 18:46 EDT 2021. Contains 345419 sequences. (Running on oeis4.)