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.

A201535 Number of nX4 0..2 arrays with rows and columns lexicographically nondecreasing and every element equal to at least one horizontal or vertical neighbor.

Table of values

n a(n)
1 6
2 69
3 633
4 7799
5 91425
6 983981
7 9526987
8 82847704
9 652848538
10 4712696751
11 31480011434
12 196280028176
13 1150650039753
14 6380377582098
15 33631853768986
16 169225758487160
17 815686475352515
18 3777731764480697
19 16854911299206527

List of values

[6, 69, 633, 7799, 91425, 983981, 9526987, 82847704, 652848538, 4712696751, 31480011434, 196280028176, 1150650039753, 6380377582098, 33631853768986, 169225758487160, 815686475352515, 3777731764480697, 16854911299206527]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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