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.

A220997 Number of n X 2 arrays of occupancy after each element stays put or moves to some horizontal or vertical neighbor.

Table of values

n a(n)
1 3
2 31
3 306
4 2989
5 29135
6 283872
7 2765627
8 26943707
9 262494146
10 2557299561
11 24914003827
12 242719929760
13 2364652602239
14 23037176752223
15 224435298485050
16 2186518067974709
17 21301735038155095
18 207528088736659200

List of values

[3, 31, 306, 2989, 29135, 283872, 2765627, 26943707, 262494146, 2557299561, 24914003827, 242719929760, 2364652602239, 23037176752223, 224435298485050, 2186518067974709, 21301735038155095, 207528088736659200]

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

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