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.

A201447 Number of nX4 0..3 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

Table of values

n a(n)
1 1
2 9
3 29
4 112
5 261
6 846
7 1720
8 4193
9 8065
10 16693
11 29073
12 55954
13 90874
14 158301
15 249828
16 409302
17 611841
18 962288
19 1392970
20 2091478
21 2957586
22 4286258
23 5893598
24 8347259
25 11221370
26 15440747
27 20464931
28 27577548
29 35834857
30 47497364
31 60856456
32 79217039

List of values

[1, 9, 29, 112, 261, 846, 1720, 4193, 8065, 16693, 29073, 55954, 90874, 158301, 249828, 409302, 611841, 962288, 1392970, 2091478, 2957586, 4286258, 5893598, 8347259, 11221370, 15440747, 20464931, 27577548, 35834857, 47497364, 60856456, 79217039]