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.

A084770 Coefficients of 1/(1-4x-16x^2)^(1/2); also, a(n) is the central coefficient of (1+2x+5x^2)^n.

Table of values

n a(n)
0 1
1 2
2 14
3 68
4 406
5 2332
6 13964
7 83848
8 509926
9 3118892
10 19194724
11 118654648
12 736365436
13 4584612632
14 28623792344
15 179142212368
16 1123532958086
17 7059622447052
18 44431918660724
19 280059644507608
20 1767597777222676

List of values

[1, 2, 14, 68, 406, 2332, 13964, 83848, 509926, 3118892, 19194724, 118654648, 736365436, 4584612632, 28623792344, 179142212368, 1123532958086, 7059622447052, 44431918660724, 280059644507608, 1767597777222676]

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

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