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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.

A201797 Number of zero-sum nX2 -2..2 arrays with every element unequal to at most two horizontal and vertical neighbors.

Table of values

n a(n)
1 5
2 85
3 455
4 3617
5 28625
6 235827
7 1972115
8 16703881
9 142672901
10 1226999941
11 10610923603
12 92180196507
13 803840798219
14 7032319990027
15 61691173120353
16 542479698511869
17 4780243712781261
18 42200307665852185
19 373156481784589911

List of values

[5, 85, 455, 3617, 28625, 235827, 1972115, 16703881, 142672901, 1226999941, 10610923603, 92180196507, 803840798219, 7032319990027, 61691173120353, 542479698511869, 4780243712781261, 42200307665852185, 373156481784589911]

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

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