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.

A238822 Number of equilateral triangles bounded by the sides and diagonals of a regular 3n-gon.

Table of values

n a(n)
1 1
2 14
3 69
4 188
5 465
6 882
7 1645
8 2648
9 4257
10 6170
11 9141
12 12564
13 17329
14 22778
15 30045
16 38192
17 48705
18 60318
19 74917
20 90740
21 110481
22 131714
23 157389
24 184968
25 217825
26 252902
27 294165
28 337988
29 388977
30 442710
31 505021
32 570464
33 645249
34 723758
35 812805
36 906012
37 1011025
38 1120658
39 1243437
40 1371080

List of values

[1, 14, 69, 188, 465, 882, 1645, 2648, 4257, 6170, 9141, 12564, 17329, 22778, 30045, 38192, 48705, 60318, 74917, 90740, 110481, 131714, 157389, 184968, 217825, 252902, 294165, 337988, 388977, 442710, 505021, 570464, 645249, 723758, 812805, 906012, 1011025, 1120658, 1243437, 1371080]

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

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