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.

A268955 Number of length-n 0..7 arrays with no repeated value equal to the previous repeated value, with new values introduced in sequential order.

Table of values

n a(n)
1 1
2 2
3 4
4 12
5 40
6 154
7 656
8 3074
9 15615
10 85314
11 497262
12 3068890
13 19899645
14 134520386
15 940841796
16 6760952170
17 49617422739
18 370013347266
19 2792665457338
20 21266237427018
21 163008076378489
22 1255477313622210
23 9703388630792784

List of values

[1, 2, 4, 12, 40, 154, 656, 3074, 15615, 85314, 497262, 3068890, 19899645, 134520386, 940841796, 6760952170, 49617422739, 370013347266, 2792665457338, 21266237427018, 163008076378489, 1255477313622210, 9703388630792784]

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

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