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A091688 Number of lattice congruences of the weak order on the Coxeter group B_n. 1
1, 2, 19, 8368, 360350697981 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

For n=0,1,2,3,4, we have a(n+1) ~ [a(n)]^3 as a very rough order-of-magnitude approximation.

LINKS

Table of n, a(n) for n=0..4.

N. Reading, Lattice congruences of the weak order.

CROSSREFS

Cf. A091687.

Sequence in context: A024229 A094663 A274762 * A306207 A073444 A301637

Adjacent sequences:  A091685 A091686 A091687 * A091689 A091690 A091691

KEYWORD

hard,more,nonn

AUTHOR

Nathan Reading (nreading(AT)umich.edu), Jan 28 2004

STATUS

approved

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Last modified December 3 20:56 EST 2020. Contains 338920 sequences. (Running on oeis4.)