

A318926


Take the binary expansion of n, starting with the least significant bit, and concatenate the lengths of the runs.


2



1, 11, 2, 21, 111, 12, 3, 31, 121, 1111, 211, 22, 112, 13, 4, 41, 131, 1121, 221, 2111, 11111, 1211, 311, 32, 122, 1112, 212, 23, 113, 14, 5, 51, 141, 1131, 231, 2121, 11121, 1221, 321, 3111
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OFFSET

1,2


COMMENTS

Obviously this compressed notation is useful only for n < 1023. A227736 is a version which works for all n.


LINKS

Table of n, a(n) for n=1..40.
Claude Lenormand, Deux transformations sur les mots, Preprint, 5 pages, Nov 17 2003. Apparently unpublished. This is a scanned copy of the version that the author sent to me in 2003.  N. J. A. Sloane, Sep 09 2018. See Procedure 1.


EXAMPLE

n, binary, run lengths, > a(n)
1, [1], [1] > 1
2, [0, 1], [1, 1] > 11
3, [1, 1], [2] > 2
4, [0, 0, 1], [2, 1] > 21
5, [1, 0, 1], [1, 1, 1] > 111
6, [0, 1, 1], [1, 2] > 12
7, [1, 1, 1], [3] > 3
8, [0, 0, 0, 1], [3, 1] > 31,
...


CROSSREFS

Cf. A227736, A101211, A318927.
Sequence in context: A303785 A262369 A092260 * A040120 A176592 A051309
Adjacent sequences: A318923 A318924 A318925 * A318927 A318928 A318929


KEYWORD

nonn,base


AUTHOR

N. J. A. Sloane, Sep 09 2018


STATUS

approved



