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.

A340685 The number of regions inside a concave circular triangle formed by the straight line segments mutually connecting all vertices and all points that divide the sides into n equal parts.

Table of values

n a(n)
1 1
2 12
3 28
4 102
5 187
6 462
7 868
8 1590
9 3046
10 4398
11 6541
12 8646
13 12256
14 15336
15 20947
16 26610
17 33478
18 41832
19 50821
20 64710
21 77110
22 97878
23 113932
24 136560
25 160849
26 185220
27 216286
28 246450
29 289945
30 324594
31 372976
32 426936
33 472231
34 537366
35 598606
36 685650
37 762736
38 858546
39 943684
40 1043442
41 1143751
42 1258800

List of values

[1, 12, 28, 102, 187, 462, 868, 1590, 3046, 4398, 6541, 8646, 12256, 15336, 20947, 26610, 33478, 41832, 50821, 64710, 77110, 97878, 113932, 136560, 160849, 185220, 216286, 246450, 289945, 324594, 372976, 426936, 472231, 537366, 598606, 685650, 762736, 858546, 943684, 1043442, 1143751, 1258800]

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

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