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 | 6 |
| 2 | 39 |
| 3 | 258 |
| 4 | 1719 |
| 5 | 11496 |
| 6 | 77052 |
| 7 | 517194 |
| 8 | 3475071 |
| 9 | 23366598 |
| 10 | 157206519 |
| 11 | 1058119992 |
| 12 | 7124428836 |
| 13 | 47983020624 |
| 14 | 323240752272 |
| 15 | 2177956129818 |
| 16 | 14677216121871 |
| 17 | 98923498131762 |
| 18 | 666819212874501 |
| 19 | 4495342330033938 |
| 20 | 30308036621747679 |
| 21 | 204356509814519712 |