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.

A239229 Euler characteristic of n-holed torus: 2 - 2*n.

Table of values

n a(n)
0 2
1 0
2 -2
3 -4
4 -6
5 -8
6 -10
7 -12
8 -14
9 -16
10 -18
11 -20
12 -22
13 -24
14 -26
15 -28
16 -30
17 -32
18 -34
19 -36
20 -38
21 -40
22 -42
23 -44
24 -46
25 -48
26 -50
27 -52
28 -54
29 -56
30 -58
31 -60
32 -62
33 -64
34 -66
35 -68
36 -70
37 -72
38 -74
39 -76
40 -78
41 -80
42 -82
43 -84
44 -86
45 -88
46 -90
47 -92
48 -94
49 -96
50 -98
51 -100
52 -102

List of values

[2, 0, -2, -4, -6, -8, -10, -12, -14, -16, -18, -20, -22, -24, -26, -28, -30, -32, -34, -36, -38, -40, -42, -44, -46, -48, -50, -52, -54, -56, -58, -60, -62, -64, -66, -68, -70, -72, -74, -76, -78, -80, -82, -84, -86, -88, -90, -92, -94, -96, -98, -100, -102]