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.

A220557 Number of ways to reciprocally link elements of an n X n array either to themselves or to exactly one horizontal or antidiagonal neighbor.

Table of values

n a(n)
1 1
2 5
3 64
4 3966
5 810778
6 665748170
7 1996515036228
8 22849956206052338
9 978504298175393645420
10 158156973836014224403041023
11 96121270674841350006417715266220

List of values

[1, 5, 64, 3966, 810778, 665748170, 1996515036228, 22849956206052338, 978504298175393645420, 158156973836014224403041023, 96121270674841350006417715266220]

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

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