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.

A199339 a(n) = number of primes with an even digit sum among the first n primes minus the number with an odd digit sum.

Table of values

n a(n)
1 1
2 0
3 -1
4 -2
5 -1
6 0
7 1
8 2
9 1
10 0
11 1
12 2
13 1
14 0
15 -1
16 0
17 1
18 0
19 -1
20 0
21 1
22 2
23 1
24 0
25 1
26 2
27 3
28 4
29 5
30 4
31 5
32 4
33 3
34 2
35 3
36 2
37 1
38 2
39 3
40 2
41 1
42 2
43 1
44 0
45 -1
46 -2
47 -1
48 -2
49 -3
50 -4
51 -3
52 -2
53 -3
54 -2
55 -1
56 -2
57 -3
58 -2
59 -1
60 -2
61 -3
62 -2
63 -1
64 -2
65 -3
66 -4
67 -5
68 -6
69 -5
70 -4
71 -5
72 -6
73 -5
74 -6

List of values

[1, 0, -1, -2, -1, 0, 1, 2, 1, 0, 1, 2, 1, 0, -1, 0, 1, 0, -1, 0, 1, 2, 1, 0, 1, 2, 3, 4, 5, 4, 5, 4, 3, 2, 3, 2, 1, 2, 3, 2, 1, 2, 1, 0, -1, -2, -1, -2, -3, -4, -3, -2, -3, -2, -1, -2, -3, -2, -1, -2, -3, -2, -1, -2, -3, -4, -5, -6, -5, -4, -5, -6, -5, -6]