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.

A199239 Number of n X n 0..2 arrays with values 0..2 introduced in row major order, the number of instances of each value within one of each other, and every element equal to zero or two horizontal or vertical neighbors.

Table of values

n a(n)
1 1
2 2
3 6
4 440
5 29227
6 1682457
7 2013526831

List of values

[1, 2, 6, 440, 29227, 1682457, 2013526831]

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

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