A121447 - cp's OEIS frontend

A121447 Level of the first leaf (in preorder traversal) of a ternary tree, summed over all ternary trees with n edges. A ternary tree is a rooted tree in which each vertex has at most three children and each child of a vertex is designated as its left or middle or right child.

n	a(n)
1	3
2	21
3	127
4	747
5	4386
6	25897
7	154077
8	923910
9	5581485
10	33949836
11	207787668
12	1278900412
13	7911394686
14	49165322241
15	306809507561
16	1921849861260
17	12079999018605
18	76170034283805
19	481680300300255
20	3054157623774495

[3, 21, 127, 747, 4386, 25897, 154077, 923910, 5581485, 33949836, 207787668, 1278900412, 7911394686, 49165322241, 306809507561, 1921849861260, 12079999018605, 76170034283805, 481680300300255, 3054157623774495]

cp's OEIS Frontend

A121447 Level of the first leaf (in preorder traversal) of a ternary tree, summed over all ternary trees with n edges. A ternary tree is a rooted tree in which each vertex has at most three children and each child of a vertex is designated as its left or middle or right child.

Table of values

List of values