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.

A087945 Expansion of (1-2x-x^2)/((1-2x)(1-4x+x^2)).

Table of values

n a(n)
0 1
1 4
2 14
3 50
4 182
5 670
6 2482
7 9226
8 34358
9 128078
10 477698
11 1782202
12 6650086
13 24816094
14 92610194
15 345616490
16 1289839382
17 4813708270
18 17964928162
19 67045873306
20 250218302918
21 933826814078
22 3485087904818
23 13006522708042

List of values

[1, 4, 14, 50, 182, 670, 2482, 9226, 34358, 128078, 477698, 1782202, 6650086, 24816094, 92610194, 345616490, 1289839382, 4813708270, 17964928162, 67045873306, 250218302918, 933826814078, 3485087904818, 13006522708042]

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

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