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.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 12 |
| 2 | 72 |
| 3 | 324 |
| 4 | 1296 |
| 5 | 4860 |
| 6 | 17496 |
| 7 | 61236 |
| 8 | 209952 |
| 9 | 708588 |
| 10 | 2361960 |
| 11 | 7794468 |
| 12 | 25509168 |
| 13 | 82904796 |
| 14 | 267846264 |
| 15 | 860934420 |
| 16 | 2754990144 |
| 17 | 8781531084 |
| 18 | 27894275208 |
| 19 | 88331871492 |
| 20 | 278942752080 |
| 21 | 878669669052 |
| 22 | 2761533245592 |
| 23 | 8661172452084 |
| 24 | 27113235502176 |
| 25 | 84728860944300 |