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A080971 A014486-encodings of the trees whose interior zigzag-tree (Stanley's c) is not branch-reduced (in the sense defined by Donaghey). 4
42, 56, 170, 172, 184, 202, 212, 226, 232, 240, 682, 684, 690, 692, 696, 714, 724, 738, 744, 752, 810, 812, 824, 842, 850, 852, 856, 880, 906, 908, 916, 930, 936, 944, 962, 964, 968, 976, 992, 2730, 2732, 2738, 2740, 2744, 2762, 2764, 2770, 2772, 2776, 2786 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

REFERENCES

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

LINKS

Table of n, a(n) for n=0..49.

A. Karttunen, Initial terms illustrated in positions 4, 8, 9, 10, 13, 14, 17, 19, 21, 22, 23, 24, 25, 26, 27, 28, 31, ...

CROSSREFS

a(n) = A014486(A080970(n)). Cf. A080981.

Sequence in context: A043916 A124656 A002706 * A039384 A043207 A043987

Adjacent sequences:  A080968 A080969 A080970 * A080972 A080973 A080974

KEYWORD

nonn

AUTHOR

Antti Karttunen Mar 02 2003

STATUS

approved

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Last modified July 21 00:49 EDT 2019. Contains 325189 sequences. (Running on oeis4.)