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.

A302260 Number of n X 3 0..1 arrays with every element equal to 0, 1, 2 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

Table of values

n a(n)
1 4
2 29
3 153
4 818
5 4386
6 23516
7 126162
8 676988
9 3632880
10 19495940
11 104627364
12 561499304
13 3013389264
14 16171937024
15 86789899608
16 465775377536
17 2499677308656
18 13415022525008
19 71994427701360
20 386372643782240
21 2073546883713888

List of values

[4, 29, 153, 818, 4386, 23516, 126162, 676988, 3632880, 19495940, 104627364, 561499304, 3013389264, 16171937024, 86789899608, 465775377536, 2499677308656, 13415022525008, 71994427701360, 386372643782240, 2073546883713888]

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

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