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A210671 Number of equivalence classes of S_n under transformations of positionally adjacent elements of the form abc <--> acb <--> bac <--> cba, where a<b<c. 6
1, 1, 2, 3, 4, 5, 8, 11, 20, 29, 57 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..10.

Steven Linton, James Propp, Tom Roby, and Julian West, Equivalence classes of permutations under various relations generated by constrained transpositions, 2011 arXiv:1111.3920 [math.CO], J. Int. Seq. 15 (2012) #12.9.1

CROSSREFS

Sequence in context: A078762 A103262 A135318 * A189761 A101137 A256386

Adjacent sequences:  A210668 A210669 A210670 * A210672 A210673 A210674

KEYWORD

nonn

AUTHOR

Tom Roby, May 08 2012

EXTENSIONS

Definition improved by Tom Roby, May 15 2012

STATUS

approved

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Last modified March 23 10:55 EDT 2019. Contains 321424 sequences. (Running on oeis4.)