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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.

A238386 a(n) = |{0 < k < n-1: p = prime(k) + pi(n-k) and p + 2 are both prime}|, where pi(.) is given by A000720.

Table of values

n a(n)
1 0
2 0
3 1
4 0
5 1
6 2
7 1
8 0
9 0
10 0
11 1
12 1
13 2
14 2
15 1
16 2
17 1
18 2
19 3
20 2
21 3
22 3
23 2
24 3
25 2
26 2
27 2
28 2
29 3
30 1
31 1
32 2
33 2
34 3
35 2
36 1
37 2
38 1
39 1
40 3
41 3
42 2
43 1
44 1
45 3
46 3
47 5
48 5
49 2
50 2
51 2
52 3
53 4
54 5
55 5
56 4
57 3
58 2
59 2
60 2
61 3
62 2
63 3
64 4
65 1
66 3
67 4
68 3
69 4
70 6
71 7
72 6
73 3
74 2
75 2
76 2
77 3
78 4
79 5
80 3

List of values

[0, 0, 1, 0, 1, 2, 1, 0, 0, 0, 1, 1, 2, 2, 1, 2, 1, 2, 3, 2, 3, 3, 2, 3, 2, 2, 2, 2, 3, 1, 1, 2, 2, 3, 2, 1, 2, 1, 1, 3, 3, 2, 1, 1, 3, 3, 5, 5, 2, 2, 2, 3, 4, 5, 5, 4, 3, 2, 2, 2, 3, 2, 3, 4, 1, 3, 4, 3, 4, 6, 7, 6, 3, 2, 2, 2, 3, 4, 5, 3]

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