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 | 621 |
| 2 | 2237 |
| 3 | 7558 |
| 4 | 26528 |
| 5 | 92748 |
| 6 | 319956 |
| 7 | 1110338 |
| 8 | 3857116 |
| 9 | 13368366 |
| 10 | 46374172 |
| 11 | 160928422 |
| 12 | 558198034 |
| 13 | 1936342232 |
| 14 | 6717789912 |
| 15 | 23304299530 |
| 16 | 80843139172 |
| 17 | 280454591492 |
| 18 | 972921980908 |
| 19 | 3375134923804 |
| 20 | 11708636231942 |
| 21 | 40618271541636 |