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.

A222840 Number of nX3 0..3 arrays with no more than floor(nX3/2) elements equal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..3 order.

Table of values

n a(n)
1 2
2 105
3 4797
4 326408
5 15364848
6 1077545438
7 52487425596
8 3689615795056
9 182579365380505
10 12856303224433084
11 643621625467714042
12 45333053732314073754
13 2288743268254953421250
14 161184278096856509113288

List of values

[2, 105, 4797, 326408, 15364848, 1077545438, 52487425596, 3689615795056, 182579365380505, 12856303224433084, 643621625467714042, 45333053732314073754, 2288743268254953421250, 161184278096856509113288]

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

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