A080970 A014486-indices of the trees whose interior zigzag-tree (Stanley's c) is not branch-reduced (in the sense defined by Donaghey).

4, 8, 9, 10, 13, 14, 17, 19, 21, 22, 23, 24, 25, 26, 27, 28, 31, 33, 35, 36, 37, 38, 41, 42, 44, 45, 46, 50, 51, 52, 54, 56, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 83, 84, 86, 87, 88, 92, 93, 94, 96, 98, 100, 101, 102, 103

Offset

0,1

Links

Table of n, a(n) for n=0..68.

Robert Donaghey, Automorphisms on Catalan trees and bracketing, J. Combin. Theory, Series B, 29 (1980), 75-90.

Formula

a(n) = A080300(A080971(n)).

Crossrefs

Cf. A014486, A080300, A080971.

See comment at A080971. Complement of A080980.

Sequence in context: A155101 A158582 A144754 * A288862 A274584 A210998

Adjacent sequences: A080967 A080968 A080969 * A080971 A080972 A080973

Keyword

nonn

Author

Antti Karttunen, Mar 02 2003

Status

approved