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.

A220635 Number of ways to reciprocally link elements of an 5Xn array either to themselves or to exactly two horizontal or antidiagonal neighbors.

Table of values

n a(n)
1 1
2 1
3 8
4 114
5 1481
6 17527
7 201903
8 2329448
9 26904225
10 310837917
11 3591561452
12 41499180881
13 479508472309
14 5540546671074
15 64018957168901
16 739714921940047
17 8547125318062702
18 98758781455779205
19 1141120102778497151

List of values

[1, 1, 8, 114, 1481, 17527, 201903, 2329448, 26904225, 310837917, 3591561452, 41499180881, 479508472309, 5540546671074, 64018957168901, 739714921940047, 8547125318062702, 98758781455779205, 1141120102778497151]

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

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