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 | 20 |
| 2 | 190 |
| 3 | 1295 |
| 4 | 7285 |
| 5 | 36122 |
| 6 | 163730 |
| 7 | 693835 |
| 8 | 2790100 |
| 9 | 10758050 |
| 10 | 40075630 |
| 11 | 145052300 |
| 12 | 512347975 |
| 13 | 1772132390 |
| 14 | 6018885570 |
| 15 | 20118711993 |
| 16 | 66306068715 |
| 17 | 215797999830 |
| 18 | 694463680160 |
| 19 | 2212291834405 |
| 20 | 6982976069384 |