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.

A137741 Number of different strings of length n+4 obtained from "123...n" by iteratively duplicating any substring.

Table of values

n a(n)
1 1
2 16
3 54
4 119
5 218
6 360
7 555
8 814
9 1149
10 1573
11 2100
12 2745
13 3524
14 4454
15 5553
16 6840
17 8335
18 10059
19 12034
20 14283
21 16830
22 19700
23 22919
24 26514
25 30513
26 34945
27 39840
28 45229
29 51144
30 57618
31 64685
32 72380
33 80739
34 89799
35 99598
36 110175
37 121570
38 133824
39 146979
40 161078

List of values

[1, 16, 54, 119, 218, 360, 555, 814, 1149, 1573, 2100, 2745, 3524, 4454, 5553, 6840, 8335, 10059, 12034, 14283, 16830, 19700, 22919, 26514, 30513, 34945, 39840, 45229, 51144, 57618, 64685, 72380, 80739, 89799, 99598, 110175, 121570, 133824, 146979, 161078]