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.

A145884 Triangle read by rows: T(n,k) is the number of Dyck paths of semilength n such that the difference between the sum of the valley abscissae and number of valleys is k (0 <= k <= (n-1)^2).

Table of values

n a(n)
0 1
1 1
2 1
3 1
4 1
5 1
6 1
7 1
8 1
9 1
10 1
11 1
12 2
13 2
14 2
15 2
16 1
17 1
18 1
19 1
20 1
21 1
22 2
23 3
24 3
25 4
26 4
27 4
28 4
29 4
30 3
31 3
32 2
33 1
34 1
35 1
36 1
37 1
38 1
39 2
40 3
41 4
42 5
43 6
44 7
45 8
46 9
47 9
48 10
49 10
50 9
51 9
52 8
53 7
54 6
55 5
56 4
57 3
58 2
59 1
60 1
61 1
62 1
63 1
64 1
65 2
66 3
67 4
68 6
69 7
70 9
71 11
72 13
73 15
74 18
75 19
76 21
77 23
78 24
79 24
80 25
81 24
82 24
83 23
84 21
85 19
86 18
87 15
88 13
89 11
90 9
91 7
92 6
93 4
94 3

List of values

[1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 2, 3, 3, 4, 4, 4, 4, 4, 3, 3, 2, 1, 1, 1, 1, 1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 9, 10, 10, 9, 9, 8, 7, 6, 5, 4, 3, 2, 1, 1, 1, 1, 1, 1, 2, 3, 4, 6, 7, 9, 11, 13, 15, 18, 19, 21, 23, 24, 24, 25, 24, 24, 23, 21, 19, 18, 15, 13, 11, 9, 7, 6, 4, 3]