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.

A201374 Number of nX7 0..1 arrays with rows and columns lexicographically nondecreasing read forwards, and nonincreasing read backwards.

Table of values

n a(n)
1 2
2 8
3 44
4 280
5 2016
6 15574
7 115168
8 728078
9 3793342
10 16517460
11 61759798
12 203474642
13 603403128
14 1638153030
15 4126393250
16 9747403504
17 21778931370
18 46349684784
19 94496712184
20 185448946836
21 351735813872
22 646956766742
23 1157359269036

List of values

[2, 8, 44, 280, 2016, 15574, 115168, 728078, 3793342, 16517460, 61759798, 203474642, 603403128, 1638153030, 4126393250, 9747403504, 21778931370, 46349684784, 94496712184, 185448946836, 351735813872, 646956766742, 1157359269036]