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A081155
Number of odd cycles in range [A014137(n-1)..A014138(n-1)] of permutation A057505/A057506, with fixed-points of both A057163 and A057164.
3
1, 1, 0, 1, 0, 2, 0, 3, 0, 6, 0, 12, 0, 20, 0, 59, 0, 120, 0
OFFSET
0,6
COMMENTS
See comment at A080973. Because A057163 can fix only binary trees of odd size, the even-indexed terms are all 0 after n>0.
FORMULA
a(n) = A081148(n)-A081153(n).
CROSSREFS
KEYWORD
nonn,more
AUTHOR
STATUS
approved