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.

A065357 a(n) = (-1)^pi(n) where pi(n) is the number of primes <= n.

Table of values

n a(n)
0 1
1 1
2 -1
3 1
4 1
5 -1
6 -1
7 1
8 1
9 1
10 1
11 -1
12 -1
13 1
14 1
15 1
16 1
17 -1
18 -1
19 1
20 1
21 1
22 1
23 -1
24 -1
25 -1
26 -1
27 -1
28 -1
29 1
30 1
31 -1
32 -1
33 -1
34 -1
35 -1
36 -1
37 1
38 1
39 1
40 1
41 -1
42 -1
43 1
44 1
45 1
46 1
47 -1
48 -1
49 -1
50 -1
51 -1
52 -1
53 1
54 1
55 1
56 1
57 1
58 1
59 -1
60 -1
61 1
62 1
63 1
64 1
65 1
66 1
67 -1
68 -1
69 -1
70 -1
71 1
72 1
73 -1
74 -1
75 -1
76 -1
77 -1
78 -1
79 1
80 1
81 1
82 1
83 -1
84 -1
85 -1
86 -1
87 -1
88 -1
89 1
90 1
91 1
92 1
93 1
94 1
95 1
96 1
97 -1
98 -1
99 -1
100 -1
101 1
102 1

List of values

[1, 1, -1, 1, 1, -1, -1, 1, 1, 1, 1, -1, -1, 1, 1, 1, 1, -1, -1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, 1, 1, -1, -1, -1, -1, -1, -1, 1, 1, 1, 1, -1, -1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, 1, 1, 1, 1, 1, 1, -1, -1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, 1, 1, -1, -1, -1, -1, -1, -1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, 1, 1]