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 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 21 |
| 5 | 73 |
| 6 | 244 |
| 7 | 786 |
| 8 | 2458 |
| 9 | 7510 |
| 10 | 22527 |
| 11 | 66579 |
| 12 | 194408 |
| 13 | 561988 |
| 14 | 1610900 |
| 15 | 4584426 |
| 16 | 12966225 |
| 17 | 36476173 |
| 18 | 102132412 |
| 19 | 284785878 |
| 20 | 791182318 |
| 21 | 2190833086 |
| 22 | 6048706947 |
| 23 | 16655647911 |
| 24 | 45752451536 |
| 25 | 125405039368 |
| 26 | 343040546984 |
| 27 | 936651104466 |
| 28 | 2553146783253 |
| 29 | 6948573570145 |