A080971 A014486-encodings of the trees whose interior zigzag-tree (Stanley's c) is not branch-reduced (in the sense defined by Donaghey).

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

Offset: 0

Author

Antti Karttunen, Mar 02 2003

Keywords

• nonn

Links

• Robert Donaghey, Automorphisms on Catalan trees and bracketing, J. Combin. Theory, Series B, 29 (1980), 75-90.
• Antti Karttunen, Initial terms illustrated in positions 4, 8, 9, 10, 13, 14, 17, 19, 21, 22, 23, 24, 25, 26, 27, 28, 31, ...

Crossrefs

Cf. A014486, A080970, A080981.

Formula

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