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.

A275831 a(n) = (sqrt(7)*csc(Pi/7)/2)^n + (-sqrt(7)*csc(2*Pi/7)/2)^n + (-sqrt(7)*csc(4*Pi/7)/2)^n.

Table of values

n a(n)
0 3
1 0
2 14
3 21
4 98
5 245
6 833
7 2401
8 7546
9 22638
10 69629
11 211288
12 645869
13 1966419
14 6000099
15 18286016
16 55765626
17 170002805
18 518361494
19 1580379017
20 4818550093
21 14691183577
22 44792503770
23 136568135690
24 416385811429
25 1269524476220
26 3870677629833
27 11801372013543
28 35981414742371
29 109704347503632
30 334479507291398

List of values

[3, 0, 14, 21, 98, 245, 833, 2401, 7546, 22638, 69629, 211288, 645869, 1966419, 6000099, 18286016, 55765626, 170002805, 518361494, 1580379017, 4818550093, 14691183577, 44792503770, 136568135690, 416385811429, 1269524476220, 3870677629833, 11801372013543, 35981414742371, 109704347503632, 334479507291398]

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

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