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A261663
Number of equivalence classes of permutations avoiding the pattern {123}.
0
1, 1, 2, 4, 8, 19, 41, 98, 221, 526
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OFFSET
0,3
COMMENTS
It seems that there is no known g.f.
LINKS
Table of n, a(n) for n=0..9.
J.-L. Baril, T. Mansour, A. Petrossian,
Equivalence classes of permutations modulo excedances
, Journal of Combinatorics, Volume 5 (2014), Number 4, doi:10.4310/JOC.2014.v5.n4.a4.
CROSSREFS
Sequence in context:
A139784
A247235
A369683
*
A199694
A037444
A151526
Adjacent sequences:
A261660
A261661
A261662
*
A261664
A261665
A261666
KEYWORD
nonn
,
more
AUTHOR
N. J. A. Sloane
, Aug 30 2015
STATUS
approved
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Last modified March 28 08:22 EDT 2024. Contains 371236 sequences. (Running on oeis4.)