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.

A120915 G.f. satisfies: A(x) = C(2x)^2 * A(x^3*C(2x)^4), where C(x) is the g.f. of the Catalan numbers (A000108).

Table of values

n a(n)
0 1
1 4
2 20
3 116
4 720
5 4656
6 30996
7 210896
8 1459536
9 10239796
10 72651184
11 520328112
12 3756512912
13 27307671040
14 199705789248
15 1468209751856
16 10844681408064
17 80437588353600
18 598867568439828
19 4473784063109904
20 33524058847464912

List of values

[1, 4, 20, 116, 720, 4656, 30996, 210896, 1459536, 10239796, 72651184, 520328112, 3756512912, 27307671040, 199705789248, 1468209751856, 10844681408064, 80437588353600, 598867568439828, 4473784063109904, 33524058847464912]

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

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