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.

A328342 a(0) = 0; for n > 1, if a(n-1) has appeared three or more times then a(n) = total number of terms between the last and second-last appearance of a(n-1), minus the total number of terms between the second-last and third-last appearance of a(n-1). If a(n-1) has appeared two times, a(n) = total number of terms between the last and second-last appearance of a(n-1). If a(n-1) has appeared once, a(n) = 0.

Table of values

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

List of values

[0, 0, 1, 0, 1, 2, 0, 1, 1, -2, 0, 1, 2, 7, 0, 0, -3, 0, 1, 4, 0, 1, -4, 0, 0, -2, 16, 0, 2, 9, 0, 0, -2, -9, 0, 2, -9, 3, 0, 1, 15, 0, -1, 0, -1, 2, 3, 9, 18, 0, 4, 31, 0, -3, 37, 0, 0, -2, 18, 10, 0, 3, 6, 0, -1, 18, -3, -24, 0, 2, 14, 0, -2, -10, 0, 0, -2, -11, 0, 2, -14]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement.