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.

A302310 Number of 2Xn 0..1 arrays with every element equal to 0, 1, 3 or 4 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

Table of values

n a(n)
1 2
2 3
3 11
4 21
5 31
6 113
7 363
8 813
9 1751
10 5001
11 14051
12 34053
13 82063
14 218273
15 579291
16 1452381
17 3638471
18 9447993
19 24526163
20 62318133
21 158325631
22 407598161
23 1049289291
24 2679681933
25 6843284663
26 17562012393
27 45069368771
28 115317418341

List of values

[2, 3, 11, 21, 31, 113, 363, 813, 1751, 5001, 14051, 34053, 82063, 218273, 579291, 1452381, 3638471, 9447993, 24526163, 62318133, 158325631, 407598161, 1049289291, 2679681933, 6843284663, 17562012393, 45069368771, 115317418341]

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

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