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.

A224808 Number of permutations (p(1), p(2), ..., p(n)) satisfying -k <= p(i)-i <= r and p(i)-i not in the set I, i=1..n, with k=2, r=6, I={-1,1,2,3,4,5}.

Table of values

n a(n)
0 1
1 1
2 1
3 1
4 1
5 1
6 1
7 2
8 4
9 6
10 9
11 12
12 16
13 20
14 25
15 35
16 49
17 70
18 100
19 140
20 196
21 266
22 361
23 494
24 676
25 936
26 1296
27 1800
28 2500
29 3450
30 4761
31 6555
32 9025
33 12445
34 17161
35 23711
36 32761
37 45250
38 62500
39 86250
40 119025
41 164220
42 226576
43 312732
44 431649
45 595899
46 822649
47 1135564
48 1567504
49 2163456
50 2985984

List of values

[1, 1, 1, 1, 1, 1, 1, 2, 4, 6, 9, 12, 16, 20, 25, 35, 49, 70, 100, 140, 196, 266, 361, 494, 676, 936, 1296, 1800, 2500, 3450, 4761, 6555, 9025, 12445, 17161, 23711, 32761, 45250, 62500, 86250, 119025, 164220, 226576, 312732, 431649, 595899, 822649, 1135564, 1567504, 2163456, 2985984]