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.

A264166 Number of (n+1) X (1+1) arrays of permutations of 0..n*2+1 with each element having directed index change 0,0 0,1 1,0 -2,-1 or -1,-2.

Table of values

n a(n)
1 1
2 4
3 8
4 16
5 33
6 69
7 145
8 300
9 624
10 1300
11 2705
12 5629
13 11713
14 24376
15 50728
16 105564
17 219681
18 457161
19 951361
20 1979800
21 4120000
22 8573800
23 17842241
24 37130041
25 77268321
26 160796844
27 334621288
28 696353256
29 1449124353
30 3015655309
31 6275635985

List of values

[1, 4, 8, 16, 33, 69, 145, 300, 624, 1300, 2705, 5629, 11713, 24376, 50728, 105564, 219681, 457161, 951361, 1979800, 4120000, 8573800, 17842241, 37130041, 77268321, 160796844, 334621288, 696353256, 1449124353, 3015655309, 6275635985]

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

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