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.

A117380 Riordan array (1/(1-4*x*c(x)),xc(x)), c(x) the g.f. of A000108.

Table of values

n a(n)
0 1
1 4
2 1
3 20
4 5
5 1
6 104
7 26
8 6
9 1
10 548
11 137
12 33
13 7
14 1
15 2904
16 726
17 178
18 41
19 8
20 1
21 15432
22 3858
23 954
24 228
25 50
26 9
27 1
28 82128
29 20532
30 5100
31 1242
32 288
33 60
34 10
35 1
36 437444
37 109361
38 27233
39 6701
40 1601
41 359
42 71
43 11
44 1
45 2331128
46 582782
47 145338
48 35977
49 8744
50 2043
51 442
52 83
53 12

List of values

[1, 4, 1, 20, 5, 1, 104, 26, 6, 1, 548, 137, 33, 7, 1, 2904, 726, 178, 41, 8, 1, 15432, 3858, 954, 228, 50, 9, 1, 82128, 20532, 5100, 1242, 288, 60, 10, 1, 437444, 109361, 27233, 6701, 1601, 359, 71, 11, 1, 2331128, 582782, 145338, 35977, 8744, 2043, 442, 83, 12]

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

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