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.

A284433 The number of positive integer sequences of length n with no duplicate substrings (forward or backward) of length greater than 1, every number different from its neighbors, and a minimal sum (= A282167(n)).

Table of values

n a(n)
1 1
2 2
3 6
4 2
5 18
6 12
7 24
8 24
9 1320
10 240
11 528
12 720
13 5664
14 105888
15 16992
16 150048
17 244800
18 4266432
19 4375296
20 39598848
21 50637312
22 123310080
23 202549248
24 15925690368
25 3765657600
26 23454351360
27 101739110400
28 437749678080
29 1572538613760
30 11891771080704
31 7862693068800
32 185042766200832

List of values

[1, 2, 6, 2, 18, 12, 24, 24, 1320, 240, 528, 720, 5664, 105888, 16992, 150048, 244800, 4266432, 4375296, 39598848, 50637312, 123310080, 202549248, 15925690368, 3765657600, 23454351360, 101739110400, 437749678080, 1572538613760, 11891771080704, 7862693068800, 185042766200832]

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

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