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.

A032094 Number of reversible strings with n-1 beads of 2 colors. 7 beads are black. String is not palindromic.

Table of values

n a(n)
9 4
10 16
11 60
12 160
13 396
14 848
15 1716
16 3200
17 5720
18 9696
19 15912
20 25152
21 38760
22 58080
23 85272
24 122496
25 173052
26 240240
27 328900
28 443872
29 592020
30 780208
31 1017900
32 1314560
33 1682928
34 2135744
35 2689808
36 3361920
37 4173840
38 5147328
39 6310128
40 7689984
41 9321780
42 11240400

List of values

[4, 16, 60, 160, 396, 848, 1716, 3200, 5720, 9696, 15912, 25152, 38760, 58080, 85272, 122496, 173052, 240240, 328900, 443872, 592020, 780208, 1017900, 1314560, 1682928, 2135744, 2689808, 3361920, 4173840, 5147328, 6310128, 7689984, 9321780, 11240400]

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

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