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.

A268954 Number of length-n 0..6 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 3073
9 15579
10 84572
11 485726
12 2918103
13 18146537
14 115772922
15 752410412
16 4954432229
17 32923518967
18 220172576536
19 1478770322954
20 9961340359315
21 67235635905765
22 454423768826774
23 3074025717951560

List of values

[1, 2, 4, 12, 40, 154, 656, 3073, 15579, 84572, 485726, 2918103, 18146537, 115772922, 752410412, 4954432229, 32923518967, 220172576536, 1478770322954, 9961340359315, 67235635905765, 454423768826774, 3074025717951560]

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

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