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.

A231747 Number of n X 2 0..2 arrays with no element less than a strict majority of its horizontal, vertical, diagonal and antidiagonal neighbors.

Table of values

n a(n)
1 3
2 15
3 51
4 186
5 687
6 2485
7 9068
8 33308
9 121445
10 444183
11 1626731
12 5949198
13 21774916
14 79713938
15 291767058
16 1068145321
17 3910543065
18 14316731138
19 52417430039
20 191916565888
21 702674552025
22 2572785049162
23 9420099176524
24 34491356066515

List of values

[3, 15, 51, 186, 687, 2485, 9068, 33308, 121445, 444183, 1626731, 5949198, 21774916, 79713938, 291767058, 1068145321, 3910543065, 14316731138, 52417430039, 191916565888, 702674552025, 2572785049162, 9420099176524, 34491356066515]

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

Content is available under The OEIS End-User License Agreement.