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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.

A265584 Array T(n,k) counting words with n letters drawn from a k-letter alphabet with no letter appearing thrice in a 3-letter subword.

Table of values

n a(n)
1 1
2 1
3 2
4 0
5 4
6 3
7 0
8 6
9 9
10 4
11 0
12 10
13 24
14 16
15 5
16 0
17 16
18 66
19 60
20 25
21 6
22 0
23 26
24 180
25 228
26 120
27 36
28 7
29 0
30 42
31 492
32 864
33 580
34 210
35 49
36 8
37 0
38 68
39 1344
40 3276
41 2800
42 1230
43 336
44 64
45 9
46 0
47 110
48 3672
49 12420
50 13520
51 7200
52 2310
53 504
54 81
55 10
56 0
57 178
58 10032
59 47088
60 65280
61 42150
62 15876
63 3976
64 720
65 100
66 11

List of values

[1, 1, 2, 0, 4, 3, 0, 6, 9, 4, 0, 10, 24, 16, 5, 0, 16, 66, 60, 25, 6, 0, 26, 180, 228, 120, 36, 7, 0, 42, 492, 864, 580, 210, 49, 8, 0, 68, 1344, 3276, 2800, 1230, 336, 64, 9, 0, 110, 3672, 12420, 13520, 7200, 2310, 504, 81, 10, 0, 178, 10032, 47088, 65280, 42150, 15876, 3976, 720, 100, 11]

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

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