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 | 0 |
| 1 | 1 |
| 2 | 9 |
| 3 | 60 |
| 4 | 467 |
| 5 | 3617 |
| 6 | 29500 |
| 7 | 248881 |
| 8 | 2155288 |
| 9 | 19016617 |
| 10 | 170169241 |
| 11 | 1539964486 |
| 12 | 14063663530 |
| 13 | 129413160100 |