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.

A270545 Number of equilateral triangle units forming perimeter of equilateral triangle.

Table of values

n a(n)
0 1
1 4
2 9
3 15
4 21
5 27
6 33
7 39
8 45
9 51
10 57
11 63
12 69
13 75
14 81
15 87
16 93
17 99
18 105
19 111
20 117
21 123
22 129
23 135
24 141
25 147
26 153
27 159
28 165
29 171
30 177
31 183
32 189
33 195
34 201
35 207
36 213
37 219
38 225
39 231
40 237
41 243
42 249
43 255
44 261
45 267
46 273
47 279
48 285
49 291
50 297
51 303
52 309
53 315

List of values

[1, 4, 9, 15, 21, 27, 33, 39, 45, 51, 57, 63, 69, 75, 81, 87, 93, 99, 105, 111, 117, 123, 129, 135, 141, 147, 153, 159, 165, 171, 177, 183, 189, 195, 201, 207, 213, 219, 225, 231, 237, 243, 249, 255, 261, 267, 273, 279, 285, 291, 297, 303, 309, 315]