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 | 22 |
| 2 | 484 |
| 3 | 10648 |
| 4 | 234256 |
| 5 | 5153632 |
| 6 | 113379904 |
| 7 | 2494357888 |
| 8 | 54875873536 |
| 9 | 1207269217792 |
| 10 | 26559922791424 |
| 11 | 584318301411328 |
| 12 | 12855002631049216 |
| 13 | 282810057883082752 |
| 14 | 6221821273427820544 |
| 15 | 136880068015412051968 |
| 16 | 3011361496339065143296 |
| 17 | 66249952919459433152512 |
| 18 | 1457498964228107529355264 |
| 19 | 32064977213018365645815808 |
| 20 | 705429498686404044207947776 |