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 | 3 |
| 2 | 8 |
| 3 | 23 |
| 4 | 73 |
| 5 | 251 |
| 6 | 920 |
| 7 | 3573 |
| 8 | 14695 |
| 9 | 64047 |
| 10 | 295792 |
| 11 | 1445659 |
| 12 | 7460349 |
| 13 | 40539363 |
| 14 | 231303192 |
| 15 | 1381924345 |
| 16 | 8623569739 |
| 17 | 56078184471 |
| 18 | 379232618512 |
| 19 | 2662012084719 |
| 20 | 19362915524849 |
| 21 | 145719545817995 |
| 22 | 1133022996552664 |
| 23 | 9090156893772893 |
| 24 | 75161929706243087 |
| 25 | 639793220810832639 |