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 | 3 |
| 2 | 2 |
| 3 | 7 |
| 4 | 16 |
| 5 | 60 |
| 6 | 201 |
| 7 | 838 |
| 8 | 3407 |
| 9 | 14767 |
| 10 | 64200 |
| 11 | 284676 |
| 12 | 1269981 |
| 13 | 5715325 |
| 14 | 25854146 |
| 15 | 117576949 |
| 16 | 536918541 |
| 17 | 2461230475 |
| 18 | 11319321354 |
| 19 | 52212782646 |