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.

A198521 Number of n X n 0..4 arrays with values 0..4 introduced in row major order and each element equal to no more than two horizontal and vertical neighbors.

Table of values

n a(n)
1 1
2 15
3 16714
4 1084539825
5 1814002928583853
6 72341858272434900016248

List of values

[1, 15, 16714, 1084539825, 1814002928583853, 72341858272434900016248]

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

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