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.

A215297 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 and column of odd squares is increasing.

Table of values

n a(n)
1 1
2 1
3 1
4 1
5 2
6 1
7 1
8 3
9 3
10 1
11 1
12 6
13 6
14 6
15 1
16 1
17 10
18 30
19 30
20 10
21 1
22 1
23 20
24 70
25 280
26 70
27 20
28 1
29 1
30 35
31 420
32 2100
33 2100
34 420
35 35
36 1
37 1
38 70
39 1050
40 23100
41 23100
42 23100
43 1050
44 70
45 1
46 1
47 126
48 6930
49 210210
50 1051050
51 1051050
52 210210
53 6930
54 126
55 1
56 1
57 252
58 18018
59 2522520
60 14294280

List of values

[1, 1, 1, 1, 2, 1, 1, 3, 3, 1, 1, 6, 6, 6, 1, 1, 10, 30, 30, 10, 1, 1, 20, 70, 280, 70, 20, 1, 1, 35, 420, 2100, 2100, 420, 35, 1, 1, 70, 1050, 23100, 23100, 23100, 1050, 70, 1, 1, 126, 6930, 210210, 1051050, 1051050, 210210, 6930, 126, 1, 1, 252, 18018, 2522520, 14294280]