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.

A240652 Number of nX4 0..1 arrays with no element equal to exactly one horizontal or vertical neighbor, with new values 0..1 introduced in row major order.

Table of values

n a(n)
1 1
2 3
3 17
4 91
5 352
6 1545
7 7154
8 33269
9 154974
10 724237
11 3394852
12 15935126
13 74854028
14 351802659
15 1653966146
16 7777530146
17 36577083726
18 172031838421
19 809149353515
20 3805931188358
21 17901967673107
22 84206433807963
23 396088887787212

List of values

[1, 3, 17, 91, 352, 1545, 7154, 33269, 154974, 724237, 3394852, 15935126, 74854028, 351802659, 1653966146, 7777530146, 36577083726, 172031838421, 809149353515, 3805931188358, 17901967673107, 84206433807963, 396088887787212]

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

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