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.

A208543 Number of n-bead necklaces of 7 colors allowing reversal, with no adjacent beads having the same color.

Table of values

n a(n)
1 7
2 21
3 35
4 231
5 777
6 4291
7 19995
8 107331
9 559895
10 3037314
11 16490775
12 90782986
13 502334385
14 2799220041
15 15672833365
16 88162676511
17 497842924845
18 2821127825971
19 16035782631855
20 91404068329560
21 522308348593785
22 2991403003191771
23 17168048327252235
24 98716281736491076

List of values

[7, 21, 35, 231, 777, 4291, 19995, 107331, 559895, 3037314, 16490775, 90782986, 502334385, 2799220041, 15672833365, 88162676511, 497842924845, 2821127825971, 16035782631855, 91404068329560, 522308348593785, 2991403003191771, 17168048327252235, 98716281736491076]

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

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