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A355911 Number of alt-unary-binary trees with n nodes. 2
1, 1, 2, 2, 2, 4, 4, 4, 4, 6, 8, 8, 8, 8, 8, 12, 12, 14, 16, 16, 16, 16, 16, 16, 24, 24, 24, 26, 28, 28, 32, 32, 32, 32, 32, 32, 32, 40 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
LINKS
Table of n, a(n) for n=1..38.
Don Knuth, Ambidextrous Numbers, Preprint, September 2022. See (13.4).
CROSSREFS
Cf. A355904-A355910, A355912, A355913.
Sequence in context: A289256 A287155 A287654 * A369207 A113402 A238726
Adjacent sequences: A355908 A355909 A355910 * A355912 A355913 A355914
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Sep 19 2022
STATUS
approved

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Last modified June 11 00:20 EDT 2024. Contains 373283 sequences. (Running on oeis4.)