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Revision History for A329866 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

Showing all changes.
Numbers whose binary expansion has its runs-resistance equal to its cuts-resistance minus 1.
(history; published version)
#7 by Susanna Cuyler at Sun Nov 24 10:00:27 EST 2019
STATUS

proposed

approved

#6 by Gus Wiseman at Sun Nov 24 00:49:11 EST 2019
STATUS

editing

proposed

#5 by Gus Wiseman at Sun Nov 24 00:48:48 EST 2019
CROSSREFS

The runsRuns-resistance of the binary expansion is A318928.

The cutsCuts-resistance of the binary expansion is A319416.

#4 by Gus Wiseman at Sun Nov 24 00:47:59 EST 2019
CROSSREFS

Compositions with runs-resistance equal to = cuts-resistance minus 1 are A329869.

#3 by Gus Wiseman at Sun Nov 24 00:46:01 EST 2019
EXAMPLE

For example, 79 has runs-resistance 3 because we have (1001111) -> (124) -> (111) -> (3), while the cuts-resistance is 4 because we have (1001111) -> (0111) -> (11) -> (1) -> (), so 79 is in the sequence.

#2 by Gus Wiseman at Sat Nov 23 19:00:34 EST 2019
NAME

allocated for Gus WisemanNumbers whose binary expansion has its runs-resistance equal to its cuts-resistance minus 1.

DATA

1, 3, 16, 30, 33, 48, 55, 56, 59, 60, 67, 68, 72, 79, 95, 97, 110, 112, 118, 120, 121, 125, 134, 135, 137, 143, 145, 158, 160, 195, 196, 219, 220, 225, 231, 241, 250, 258, 270, 280, 286, 291, 292, 315, 316, 351, 381, 382, 390, 391, 393, 399, 415, 416, 431, 432

OFFSET

1,2

COMMENTS

For the operation of taking the sequence of run-lengths of a finite sequence, runs-resistance is defined to be the number of applications required to reach a singleton.

For the operation of shortening all runs by 1, cuts-resistance is defined to be the number of applications required to reach an empty word.

LINKS

Claude Lenormand, <a href="/A318921/a318921.pdf">Deux transformations sur les mots</a>, Preprint, 5 pages, Nov 17 2003.

EXAMPLE

The sequence of terms together with their binary expansions begins:

1: 1

3: 11

16: 10000

30: 11110

33: 100001

48: 110000

55: 110111

56: 111000

59: 111011

60: 111100

67: 1000011

68: 1000100

72: 1001000

79: 1001111

95: 1011111

97: 1100001

110: 1101110

112: 1110000

118: 1110110

120: 1111000

MATHEMATICA

runsres[q_]:=Length[NestWhileList[Length/@Split[#]&, q, Length[#]>1&]]-1;

degdep[q_]:=Length[NestWhileList[Join@@Rest/@Split[#]&, q, Length[#]>0&]]-1;

Select[Range[100], runsres[IntegerDigits[#, 2]]-degdep[IntegerDigits[#, 2]]==-1&]

CROSSREFS

Positions of -1's in A329867.

The version for runs-resistance equal to cuts-resistance is A329865.

Compositions with runs-resistance equal to cuts-resistance are A329864.

Compositions with runs-resistance equal to cuts-resistance minus 1 are A329869.

The runs-resistance of the binary expansion is A318928.

The cuts-resistance of the binary expansion is A319416.

Compositions counted by runs-resistance are A329744.

Compositions counted by cuts-resistance are A329861.

Binary words counted by runs-resistance are A319411 and A329767.

Binary words counted by cuts-resistance are A319421 and A329860.

Cf. A000975, A003242, A107907, A164707, A329738, A329868.

KEYWORD

allocated

nonn

AUTHOR

Gus Wiseman, Nov 23 2019

STATUS

approved

editing

#1 by Gus Wiseman at Fri Nov 22 23:24:20 EST 2019
NAME

allocated for Gus Wiseman

KEYWORD

allocated

STATUS

approved