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URL: https://oeis.org/A224255

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A224255
Number of permutations w in S_n whose Kazhdan-Lusztig polynomial evaluated at q=1 is less than or equal to 2; P_{id,w}(1) <= 2.
1
1, 2, 6, 24, 115, 590, 3050, 15576, 78318, 388208
OFFSET
1,2
COMMENTS
This family of permutations is characterized by a finite set of patterns.
REFERENCES
S. Billey and T. Braden, Lower bounds for Kazhdan-Lusztig polynomials from patterns, Transform. Groups 8 (2003), no. 4, 321-332.
CROSSREFS
Cf. A224316.
Sequence in context: A177522 A216717 A174072 * A326348 A128088 A069657
KEYWORD
nonn,more
AUTHOR
Sara Billey, Apr 03 2013
STATUS
approved