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) |
|---|---|
| 8 | 1 |
| 9 | 12 |
| 10 | 94 |
| 11 | 604 |
| 12 | 3463 |
| 13 | 18440 |
| 14 | 93274 |
| 15 | 454412 |
| 16 | 2151673 |
| 17 | 9964500 |
| 18 | 45335002 |
| 19 | 203303760 |
| 20 | 900901387 |
| 21 | 3952468348 |
| 22 | 17194102478 |
| 23 | 74257185512 |
| 24 | 318693463933 |
| 25 | 1360298775524 |
| 26 | 5778468266446 |
| 27 | 24442845038580 |