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 | 300 |
| 4 | 990 |
| 5 | 2772 |
| 6 | 6864 |
| 7 | 15444 |
| 8 | 32175 |
| 9 | 62920 |
| 10 | 116688 |
| 11 | 206856 |
| 12 | 352716 |
| 13 | 581400 |
| 14 | 930240 |
| 15 | 1449624 |
| 16 | 2206413 |
| 17 | 3287988 |
| 18 | 4807000 |
| 19 | 6906900 |
| 20 | 9768330 |
| 21 | 13616460 |
| 22 | 18729360 |
| 23 | 25447500 |
| 24 | 34184475 |
| 25 | 45439056 |
| 26 | 59808672 |
| 27 | 78004432 |
| 28 | 100867800 |
| 29 | 129389040 |
| 30 | 164727552 |
| 31 | 208234224 |