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.

A269290 Number of 2 X n 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three no more than once.

Table of values

n a(n)
1 16
2 216
3 2124
4 19188
5 164556
6 1363572
7 11026764
8 87559668
9 685523916
10 5306911092
11 40706083404
12 309846524148
13 2343253251276
14 17623065834612
15 131903512372044
16 983118947312628
17 7300393156146636
18 54032675767734132
19 398738196097092684

List of values

[16, 216, 2124, 19188, 164556, 1363572, 11026764, 87559668, 685523916, 5306911092, 40706083404, 309846524148, 2343253251276, 17623065834612, 131903512372044, 983118947312628, 7300393156146636, 54032675767734132, 398738196097092684]

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

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