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A080980 A014486-indices of the trees whose interior zigzag-tree (Stanley's c) is branch-reduced (in the sense defined by Donaghey). 4
0, 1, 2, 3, 5, 6, 7, 11, 12, 15, 16, 18, 20, 29, 30, 32, 34, 39, 40, 43, 47, 48, 49, 53, 55, 57, 81, 82, 85, 89, 90, 91, 95, 97, 99, 113, 114, 116, 118, 123, 124, 136, 137, 139, 140, 141, 143, 146, 155, 159, 160, 161, 165, 167, 173, 183, 245, 246, 248, 250, 255, 256, 268 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

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..62.

R. P. Stanley, Exercises on Catalan and Related Numbers

CROSSREFS

Cf. A080979. a(n) = A080300(A080981(n)). See comment at A080981. Complement of A080970.

Sequence in context: A243058 A288863 A121700 * A134669 A053328 A089633

Adjacent sequences:  A080977 A080978 A080979 * A080981 A080982 A080983

KEYWORD

nonn

AUTHOR

Antti Karttunen Mar 02 2003

STATUS

approved

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Last modified May 26 05:25 EDT 2019. Contains 323579 sequences. (Running on oeis4.)