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 | 2 |
| 2 | 13 |
| 3 | 70 |
| 4 | 336 |
| 5 | 2076 |
| 6 | 11091 |
| 7 | 65210 |
| 8 | 365661 |
| 9 | 2159354 |
| 10 | 11713047 |
| 11 | 71427504 |
| 12 | 392916687 |
| 13 | 2245186352 |
| 14 | 13527678851 |
| 15 | 73679458270 |
| 16 | 429472428457 |
| 17 | 2553994191220 |
| 18 | 14264421153074 |
| 19 | 80483620074092 |
| 20 | 489077890675807 |
| 21 | 2768919905996888 |
| 22 | 15394229582049408 |
| 23 | 91794448088043258 |