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.

A302473 Number of 3Xn 0..1 arrays with every element equal to 1, 2, 3 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

Table of values

n a(n)
1 0
2 11
3 49
4 203
5 955
6 4556
7 21843
8 103319
9 491073
10 2332753
11 11082938
12 52648987
13 250106679
14 1188163911
15 5644397853
16 26814116700
17 127381683511
18 605134192403
19 2874722191055
20 13656526930929
21 64876076932622
22 308197362006435

List of values

[0, 11, 49, 203, 955, 4556, 21843, 103319, 491073, 2332753, 11082938, 52648987, 250106679, 1188163911, 5644397853, 26814116700, 127381683511, 605134192403, 2874722191055, 13656526930929, 64876076932622, 308197362006435]

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

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