A131890 - cp's OEIS frontend

A131890 a(n) is the number of shapes of balanced trees with constant branching factor 4 and n nodes. The node is balanced if the size, measured in nodes, of each pair of its children differ by at most one node.

n	a(n)
0	1
1	1
2	4
3	6
4	4
5	1
6	16
7	96
8	256
9	256
10	1536
11	3456
12	3456
13	1296
14	3456
15	3456
16	1536
17	256
18	256
19	96
20	16
21	1
22	64
23	1536
24	16384
25	65536
26	1572864
27	14155776
28	56623104
29	84934656
30	905969664
31	3623878656
32	6442450944
33	4294967296
34	17179869184
35	25769803776
36	17179869184
37	4294967296

[1, 1, 4, 6, 4, 1, 16, 96, 256, 256, 1536, 3456, 3456, 1296, 3456, 3456, 1536, 256, 256, 96, 16, 1, 64, 1536, 16384, 65536, 1572864, 14155776, 56623104, 84934656, 905969664, 3623878656, 6442450944, 4294967296, 17179869184, 25769803776, 17179869184, 4294967296]

cp's OEIS Frontend

A131890 a(n) is the number of shapes of balanced trees with constant branching factor 4 and n nodes. The node is balanced if the size, measured in nodes, of each pair of its children differ by at most one node.

Table of values

List of values