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.

A231840 Number of 2Xn 0..3 arrays with no element less than a strict majority of its horizontal and antidiagonal neighbors.

Table of values

n a(n)
1 16
2 50
3 188
4 760
5 3309
6 14666
7 64607
8 283479
9 1243280
10 5452114
11 23905237
12 104828007
13 459770373
14 2016638186
15 8845269109
16 38796696140
17 170170211095
18 746407664707
19 3273942709889
20 14360456936977
21 62989372397071

List of values

[16, 50, 188, 760, 3309, 14666, 64607, 283479, 1243280, 5452114, 23905237, 104828007, 459770373, 2016638186, 8845269109, 38796696140, 170170211095, 746407664707, 3273942709889, 14360456936977, 62989372397071]

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

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