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.

A067648 Number of knot diagrams of type 2PI with n crossings and two outgoing strings.

Table of values

n a(n)
0 0
1 2
2 0
3 2
4 4
5 12
6 60
7 226
8 1076
9 5156
10 24984
11 128548
12 663040
13 3514968
14 18918792
15 103123906
16 569877652
17 3180066004
18 17921451960
19 101842206548
20 583109887600
21 3361640932872
22 19499226668816

List of values

[0, 2, 0, 2, 4, 12, 60, 226, 1076, 5156, 24984, 128548, 663040, 3514968, 18918792, 103123906, 569877652, 3180066004, 17921451960, 101842206548, 583109887600, 3361640932872, 19499226668816]

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

Content is available under The OEIS End-User License Agreement.