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.

A014409 Number of inequivalent ways (mod D_4) a pair of checkers can be placed on an n X n board.

Table of values

n a(n)
1 0
2 2
3 8
4 21
5 49
6 93
7 171
8 278
9 446
10 660
11 970
12 1347
13 1863
14 2471
15 3269
16 4188
17 5356
18 6678
19 8316
20 10145
21 12365
22 14817
23 17743
24 20946
25 24714
26 28808
27 33566
28 38703
29 44611
30 50955
31 58185
32 65912
33 74648
34 83946
35 94384
36 105453
37 117801
38 130853
39 145331
40 160590
41 177430
42 195132

List of values

[0, 2, 8, 21, 49, 93, 171, 278, 446, 660, 970, 1347, 1863, 2471, 3269, 4188, 5356, 6678, 8316, 10145, 12365, 14817, 17743, 20946, 24714, 28808, 33566, 38703, 44611, 50955, 58185, 65912, 74648, 83946, 94384, 105453, 117801, 130853, 145331, 160590, 177430, 195132]