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.

A301902 Number of n X 3 0..1 arrays with every element equal to 0, 2 or 3 horizontally or antidiagonally adjacent elements, with upper left element zero.

Table of values

n a(n)
1 1
2 2
3 3
4 7
5 16
6 43
7 117
8 330
9 935
10 2667
11 7616
12 21775
13 62273
14 178130
15 509563
16 1457727
17 4170224
18 11930147
19 34129757
20 97638522
21 279324735
22 799093699
23 2286051744
24 6539949991
25 18709526921
26 53524323778
27 153122698291
28 438054310967

List of values

[1, 2, 3, 7, 16, 43, 117, 330, 935, 2667, 7616, 21775, 62273, 178130, 509563, 1457727, 4170224, 11930147, 34129757, 97638522, 279324735, 799093699, 2286051744, 6539949991, 18709526921, 53524323778, 153122698291, 438054310967]

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

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