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.

A302164 Number of 2Xn 0..1 arrays with every element equal to 0, 1 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

Table of values

n a(n)
1 2
2 3
3 9
4 17
5 25
6 65
7 185
8 385
9 649
10 1489
11 3929
12 8609
13 15913
14 34545
15 85497
16 191809
17 377545
18 802961
19 1894553
20 4279521
21 8785769
22 18612785
23 42501945
24 95817857
25 202153993
26 429672401
27 960801241
28 2153871393
29 4621792425
30 9879318897

List of values

[2, 3, 9, 17, 25, 65, 185, 385, 649, 1489, 3929, 8609, 15913, 34545, 85497, 191809, 377545, 802961, 1894553, 4279521, 8785769, 18612785, 42501945, 95817857, 202153993, 429672401, 960801241, 2153871393, 4621792425, 9879318897]

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

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