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.

A284731 Square array read by antidiagonals downwards: T(n,k) = number of linear extensions of the North-East rectangular partial order NE_{n,k} that avoid the pattern 123.

Table of values

n a(n)
1 1
2 1
3 1
4 1
5 2
6 1
7 1
8 5
9 5
10 1
11 1
12 14
13 33
14 14
15 1
16 1
17 42
18 234
19 238
20 42
21 1
22 1
23 132
24 1706
25 4146
26 1782
27 132
28 1

List of values

[1, 1, 1, 1, 2, 1, 1, 5, 5, 1, 1, 14, 33, 14, 1, 1, 42, 234, 238, 42, 1, 1, 132, 1706, 4146, 1782, 132, 1]