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 | 1 |
| 2 | 5 |
| 3 | 55 |
| 4 | 969 |
| 5 | 23751 |
| 6 | 749398 |
| 7 | 28989675 |
| 8 | 1329890705 |
| 9 | 70625252863 |
| 10 | 4263421511271 |
| 11 | 288417894029200 |
| 12 | 21616536107173175 |
| 13 | 1778197364075525550 |
| 14 | 159297460456229992380 |
| 15 | 15438280311293473537331 |
| 16 | 1609484153977526457766689 |
| 17 | 179612918129148904884024975 |