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.

A056454 Number of palindromes of length n using exactly three different symbols.

Table of values

n a(n)
1 0
2 0
3 0
4 0
5 6
6 6
7 36
8 36
9 150
10 150
11 540
12 540
13 1806
14 1806
15 5796
16 5796
17 18150
18 18150
19 55980
20 55980
21 171006
22 171006
23 519156
24 519156
25 1569750
26 1569750
27 4733820
28 4733820
29 14250606
30 14250606
31 42850116
32 42850116
33 128746950
34 128746950
35 386634060
36 386634060
37 1160688606

List of values

[0, 0, 0, 0, 6, 6, 36, 36, 150, 150, 540, 540, 1806, 1806, 5796, 5796, 18150, 18150, 55980, 55980, 171006, 171006, 519156, 519156, 1569750, 1569750, 4733820, 4733820, 14250606, 14250606, 42850116, 42850116, 128746950, 128746950, 386634060, 386634060, 1160688606]

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

Content is available under The OEIS End-User License Agreement.