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.

A156749 For all numbers k(n) congruent to -1 or +1 (mod 4) starting with k(n) = {3,5,7,9,11,...}, a(k(n)) is incremented by the congruence (mod 4) if k(n) is prime and by 0 if k(n) is composite.

Table of values

n a(n)
1 -1
2 0
3 -1
4 -1
5 -2
6 -1
7 -1
8 0
9 -1
10 -1
11 -2
12 -2
13 -2
14 -1
15 -2
16 -2
17 -2
18 -1
19 -1
20 0
21 -1
22 -1
23 -2
24 -2
25 -2
26 -1
27 -1
28 -1
29 -2
30 -1
31 -1
32 -1
33 -2
34 -2
35 -3
36 -2
37 -2
38 -2
39 -3
40 -3
41 -4
42 -4
43 -4
44 -3
45 -3
46 -3
47 -3
48 -2
49 -2
50 -1
51 -2
52 -2
53 -3
54 -2
55 -2
56 -1
57 -1
58 -1
59 -1
60 -1
61 -1
62 -1
63 -2
64 -2
65 -3
66 -3
67 -3
68 -2
69 -3
70 -3

List of values

[-1, 0, -1, -1, -2, -1, -1, 0, -1, -1, -2, -2, -2, -1, -2, -2, -2, -1, -1, 0, -1, -1, -2, -2, -2, -1, -1, -1, -2, -1, -1, -1, -2, -2, -3, -2, -2, -2, -3, -3, -4, -4, -4, -3, -3, -3, -3, -2, -2, -1, -2, -2, -3, -2, -2, -1, -1, -1, -1, -1, -1, -1, -2, -2, -3, -3, -3, -2, -3, -3]