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.

A047140 Array read by diagonals: T(h,k)=number of paths consisting of steps from (0,0) to (h,k) such that each step has length 1 directed up or right and no up-step crosses the line y=4x/3. (Thus a path crosses the line only at lattice points and on right-steps.).

Table of values

n a(n)
0 1
1 1
2 1
3 1
4 2
5 1
6 1
7 1
8 3
9 1
10 1
11 2
12 4
13 4
14 1
15 1
16 3
17 2
18 8
19 5
20 1
21 1
22 4
23 5
24 10
25 13
26 6
27 1
28 1
29 5
30 9
31 15
32 23
33 19
34 7
35 1
36 1
37 6
38 14
39 24
40 38
41 42
42 26
43 8
44 1
45 1
46 7
47 20
48 38
49 62
50 80
51 68
52 34
53 9
54 1
55 1
56 8
57 27
58 58
59 38
60 142
61 148
62 102
63 43
64 10
65 1
66 1
67 9
68 35
69 85
70 96
71 180
72 290

List of values

[1, 1, 1, 1, 2, 1, 1, 1, 3, 1, 1, 2, 4, 4, 1, 1, 3, 2, 8, 5, 1, 1, 4, 5, 10, 13, 6, 1, 1, 5, 9, 15, 23, 19, 7, 1, 1, 6, 14, 24, 38, 42, 26, 8, 1, 1, 7, 20, 38, 62, 80, 68, 34, 9, 1, 1, 8, 27, 58, 38, 142, 148, 102, 43, 10, 1, 1, 9, 35, 85, 96, 180, 290]