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.

A023421 Generalized Catalan Numbers x^2*A(x)^2 -(1-x+x^2+x^3+x^4)*A(x) + 1 =0.

Table of values

n a(n)
0 1
1 1
2 1
3 1
4 1
5 2
6 4
7 8
8 16
9 32
10 65
11 133
12 274
13 568
14 1184
15 2481
16 5223
17 11042
18 23434
19 49908
20 106633
21 228505
22 490999
23 1057683
24 2283701
25 4941502
26 10713941
27 23272929
28 50642017
29 110377543
30 240944076
31 526717211
32 1152996206
33 2527166334
34 5545804784
35 12184053993

List of values

[1, 1, 1, 1, 1, 2, 4, 8, 16, 32, 65, 133, 274, 568, 1184, 2481, 5223, 11042, 23434, 49908, 106633, 228505, 490999, 1057683, 2283701, 4941502, 10713941, 23272929, 50642017, 110377543, 240944076, 526717211, 1152996206, 2527166334, 5545804784, 12184053993]