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A091687 Number of lattice congruences of the weak order on the Coxeter group S_n (the symmetric group). 4
1, 2, 7, 60, 3444, 11402948, 129187106461769 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
To a very good approximation for n=4,5,6 we have a(n+1) ~ (a(n))^2.
LINKS
Nathan Reading, Lattice congruences of the weak order, arXiv:math/0401404 [math.CO], 2004.
CROSSREFS
Sequence in context: A352625 A308681 A366328 * A000892 A211875 A065397
KEYWORD
nonn,hard,more
AUTHOR
Nathan Reading (nreading(AT)umich.edu), Jan 28 2004
STATUS
approved

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Last modified May 23 09:20 EDT 2024. Contains 372760 sequences. (Running on oeis4.)