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.

A268898 Number of n X 2 0..2 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once.

Table of values

n a(n)
1 3
2 36
3 240
4 1344
5 6912
6 33792
7 159744
8 737280
9 3342336
10 14942208
11 66060288
12 289406976
13 1258291200
14 5435817984
15 23353884672
16 99857989632
17 425201762304
18 1803886264320
19 7627861917696
20 32160715112448
21 135239930216448

List of values

[3, 36, 240, 1344, 6912, 33792, 159744, 737280, 3342336, 14942208, 66060288, 289406976, 1258291200, 5435817984, 23353884672, 99857989632, 425201762304, 1803886264320, 7627861917696, 32160715112448, 135239930216448]

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

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