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.

A109468 a(n) is the number of permutations of (1,2,3,...,n) written in binary such that no adjacent elements share a common 1-bit.

Table of values

n a(n)
1 1
2 2
3 0
4 4
5 2
6 0
7 0
8 0
9 8
10 32
11 0
12 8
13 0
14 0
15 0
16 0
17 0
18 64
19 0
20 1968
21 508
22 0
23 0
24 0
25 16
26 0
27 0
28 0
29 0
30 0
31 0
32 0
33 0
34 0
35 0
36 0
37 1024
38 0
39 0
40 0

List of values

[1, 2, 0, 4, 2, 0, 0, 0, 8, 32, 0, 8, 0, 0, 0, 0, 0, 64, 0, 1968, 508, 0, 0, 0, 16, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1024, 0, 0, 0]