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.

A260296 Sum over the genera g of the number of immersions of an oriented circle with n crossing in an oriented surface of genus g.

Table of values

n a(n)
1 1
2 4
3 22
4 218
5 3028
6 55540
7 1235526
8 32434108
9 980179566
10 33522177088
11 1279935820810
12 53970628896500
13 2490952020480012
14 124903451391713412
15 6761440164391403896
16 393008709559373134184
17 24412776311194951680016
18 1613955767240361647220648
19 113146793787569865523200018
20 8384177419658944198600637096

List of values

[1, 4, 22, 218, 3028, 55540, 1235526, 32434108, 980179566, 33522177088, 1279935820810, 53970628896500, 2490952020480012, 124903451391713412, 6761440164391403896, 393008709559373134184, 24412776311194951680016, 1613955767240361647220648, 113146793787569865523200018, 8384177419658944198600637096]

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

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