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 | 2 |
| 2 | 5 |
| 3 | 19 |
| 4 | 113 |
| 5 | 966 |
| 6 | 10958 |
| 7 | 156700 |
| 8 | 2727794 |
| 9 | 56306696 |
| 10 | 1350043965 |
| 11 | 36979531549 |
| 12 | 1141573025172 |
| 13 | 39272377323693 |
| 14 | 1491452150268436 |
| 15 | 62027842189908231 |
| 16 | 2805631215820328992 |
| 17 | 137199563717151509077 |
| 18 | 7215932308408758314447 |