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.

A240889 Number of nX4 0..2 arrays with no element equal to a different number of vertical neighbors than horizontal neighbors, with new values 0..2 introduced in row major order.

Table of values

n a(n)
1 4
2 36
3 289
4 2362
5 19065
6 154858
7 1255585
8 10186158
9 82615013
10 670126562
11 5435464261
12 44088312610
13 357608156789
14 2900631278142
15 23527575671521
16 190836751334954
17 1547913820098569
18 12555429390762018
19 101839521640750945

List of values

[4, 36, 289, 2362, 19065, 154858, 1255585, 10186158, 82615013, 670126562, 5435464261, 44088312610, 357608156789, 2900631278142, 23527575671521, 190836751334954, 1547913820098569, 12555429390762018, 101839521640750945]

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

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