cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A221857 Number A(n,k) of shapes of balanced k-ary trees with n nodes, where a tree is balanced if the total number of nodes in subtrees corresponding to the branches of any node differ by at most one; square array A(n,k), n>=0, k>=0, read by antidiagonals.

Table of values

n a(n)
0 1
1 1
2 1
3 1
4 1
5 0
6 1
7 1
8 1
9 0
10 1
11 1
12 2
13 1
14 0
15 1
16 1
17 3
18 1
19 1
20 0
21 1
22 1
23 4
24 3
25 4
26 1
27 0
28 1
29 1
30 5
31 6
32 1
33 4
34 1
35 0
36 1
37 1
38 6
39 10
40 4
41 9
42 4
43 1
44 0
45 1
46 1
47 7
48 15
49 10
50 1
51 27
52 1
53 1
54 0
55 1
56 1
57 8
58 21
59 20
60 5
61 16
62 27
63 8
64 1
65 0
66 1
67 1
68 9
69 28
70 35
71 15
72 1
73 96
74 81
75 16
76 1
77 0
78 1
79 1
80 10
81 36
82 56
83 35
84 6
85 25
86 256
87 81
88 32
89 1
90 0

List of values

[1, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 2, 1, 0, 1, 1, 3, 1, 1, 0, 1, 1, 4, 3, 4, 1, 0, 1, 1, 5, 6, 1, 4, 1, 0, 1, 1, 6, 10, 4, 9, 4, 1, 0, 1, 1, 7, 15, 10, 1, 27, 1, 1, 0, 1, 1, 8, 21, 20, 5, 16, 27, 8, 1, 0, 1, 1, 9, 28, 35, 15, 1, 96, 81, 16, 1, 0, 1, 1, 10, 36, 56, 35, 6, 25, 256, 81, 32, 1, 0]