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.

A215870 T(n,k) = Number of permutations of 0..floor((n*k-2)/2) on odd squares of an n X k array such that each row, column, diagonal and (downwards) antidiagonal of odd squares is increasing.

Table of values

n a(n)
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 1
14 1
15 1
16 1
17 2
18 2
19 1
20 1
21 1
22 1
23 5
24 4
25 4
26 1
27 1
28 1
29 1
30 5
31 12
32 10
33 4
34 1
35 1
36 1
37 1
38 14
39 29
40 78
41 20
42 8
43 1
44 1
45 1
46 1
47 14
48 110
49 262
50 189
51 50
52 8
53 1
54 1
55 1
56 1
57 42
58 290
59 3001
60 1642
61 1233
62 100
63 16
64 1
65 1
66 1
67 1
68 42
69 1274
70 11694
71 26451
72 15485
73 2988
74 250
75 16
76 1
77 1
78 1
79 1
80 132

List of values

[1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 5, 4, 4, 1, 1, 1, 1, 5, 12, 10, 4, 1, 1, 1, 1, 14, 29, 78, 20, 8, 1, 1, 1, 1, 14, 110, 262, 189, 50, 8, 1, 1, 1, 1, 42, 290, 3001, 1642, 1233, 100, 16, 1, 1, 1, 1, 42, 1274, 11694, 26451, 15485, 2988, 250, 16, 1, 1, 1, 1, 132]