The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A043879

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A043879

Numbers k such that 1 and 2 occur juxtaposed in the base-3 representation of k but not of k+1.
(history; published version)

#13 by Jon E. Schoenfield at Wed Aug 25 04:52:51 EDT 2021

STATUS

reviewed

approved

#12 by Joerg Arndt at Wed Aug 25 03:55:14 EDT 2021

STATUS

proposed

reviewed

#11 by Michel Marcus at Wed Aug 25 02:11:28 EDT 2021

STATUS

editing

proposed

#10 by Michel Marcus at Wed Aug 25 02:11:26 EDT 2021

CROSSREFS

Cf. A007089.

STATUS

proposed

editing

#9 by Jon E. Schoenfield at Wed Aug 25 00:49:25 EDT 2021

STATUS

editing

proposed

#8 by Jon E. Schoenfield at Wed Aug 25 00:49:23 EDT 2021

NAME

Numbers n k such that 1 and 2 occur juxtaposed in the base -3 representation of n k but not of nk+1.

STATUS

approved

editing

#7 by Harvey P. Dale at Mon Jun 18 11:24:08 EDT 2018

STATUS

editing

approved

#6 by Harvey P. Dale at Mon Jun 18 11:24:05 EDT 2018

MATHEMATICA

SequencePosition[Table[If[SequenceCount[IntegerDigits[n, 3], {1, 2}]>0 || SequenceCount[IntegerDigits[n, 3], {2, 1}]>0, 1, 0], {n, 400}], {1, 0}][[All, 1]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jun 18 2018 *)

STATUS

approved

editing

#5 by Russ Cox at Fri Mar 30 18:56:40 EDT 2012

AUTHOR

Clark Kimberling (ck6(AT)evansville.edu)

Clark Kimberling

Discussion

Fri Mar 30

18:56

OEIS Server: https://oeis.org/edit/global/285

#4 by N. J. A. Sloane at Fri May 11 03:00:00 EDT 2007

NAME

Numbers n such that 1 and 2 occur juxtaposed in the base 3 representation of n but not of n+1.

KEYWORD

nonn,base,new