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 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 30 |
| 5 | 189 |
| 6 | 217 |
| 7 | 2225 |
| 8 | 3385 |
| 9 | 14357 |
| 10 | 30802 |
| 11 | 31545 |
| 12 | 104071 |
| 13 | 149689 |
| 14 | 1094421 |
| 15 | 1319945 |
| 16 | 10655462 |
| 17 | 23163298 |
| 18 | 112228683 |
| 19 | 182837804 |
| 20 | 203615628 |
| 21 | 486570087 |
| 22 | 1094330259 |
| 23 | 11992433550 |
| 24 | 17883926781 |
| 25 | 50070452577 |
| 26 | 52302956123 |
| 27 | 72178455400 |
| 28 | 94906079600 |
| 29 | 473258870471 |
| 30 | 662221289043 |