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A081164
Number of distinct cycle lengths in range [A014137(n-1)..A014138(n-1)] of permutation A057505/A057506.
3
1, 1, 1, 2, 2, 4, 4, 11, 15, 25, 32, 64, 88, 155, 234, 423, 647, 1184, 1800
OFFSET
0,4
COMMENTS
This is the number of nonzero, non-constant terms of the polynomials M_n(x) Donaghey gives on the page 81 of his paper. The term x^18 seems to have been accidentally dropped from the polynomial M_7(x).
LINKS
Robert Donaghey, Automorphisms on Catalan trees and bracketing, J. Combin. Theory, Series B, 29 (1980), 75-90.
CROSSREFS
Sequence in context: A209284 A321468 A288044 * A125553 A218147 A226978
KEYWORD
nonn,more
AUTHOR
STATUS
approved