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) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 6 |
| 5 | 9 |
| 6 | 56 |
| 7 | 51 |
| 8 | 258 |
| 9 | 380 |
| 10 | 1500 |
| 11 | 1611 |
| 12 | 12298 |
| 13 | 10245 |
| 14 | 57108 |
| 15 | 121721 |
| 16 | 346146 |
| 17 | 474489 |
| 18 | 3589534 |
| 19 | 3397143 |
| 20 | 21984804 |
| 21 | 41570773 |
| 22 | 142619388 |
| 23 | 186027579 |
| 24 | 1476414178 |
| 25 | 1694455320 |
| 26 | 8146633638 |
| 27 | 15690141155 |