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.

A249873 In decimal representation: replace each even positioned digit with the digit sum of its double.

Table of values

n a(n)
0 0
1 1
2 2
3 3
4 4
5 5
6 6
7 7
8 8
9 9
10 20
11 21
12 22
13 23
14 24
15 25
16 26
17 27
18 28
19 29
20 40
21 41
22 42
23 43
24 44
25 45
26 46
27 47
28 48
29 49
30 60
31 61
32 62
33 63
34 64
35 65
36 66
37 67
38 68
39 69
40 80
41 81
42 82
43 83
44 84
45 85
46 86
47 87
48 88
49 89
50 10
51 11
52 12
53 13
54 14
55 15
56 16
57 17
58 18
59 19
60 30
61 31
62 32
63 33
64 34
65 35
66 36

List of values

[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 30, 31, 32, 33, 34, 35, 36]

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

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