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.

A243600 Number of length n+2 0..3 arrays with no three elements in a row with pattern aba (with a!=b) and new values 0..3 introduced in 0..3 order.

Table of values

n a(n)
1 4
2 10
3 28
4 85
5 269
6 870
7 2844
8 9346
9 30792
10 101577
11 335289
12 1107066
13 3655876
14 12073706
15 39875396
16 131697309
17 434963141
18 1436579966
19 4744692092
20 15670638530
21 51756579024
22 170940329233
23 564577491697
24 1864672682930
25 6158595344068

List of values

[4, 10, 28, 85, 269, 870, 2844, 9346, 30792, 101577, 335289, 1107066, 3655876, 12073706, 39875396, 131697309, 434963141, 1436579966, 4744692092, 15670638530, 51756579024, 170940329233, 564577491697, 1864672682930, 6158595344068]

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

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