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 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 9 |
| 6 | 22 |
| 7 | 71 |
| 8 | 217 |
| 9 | 729 |
| 10 | 2438 |
| 11 | 8440 |
| 12 | 29414 |
| 13 | 104138 |
| 14 | 371516 |
| 15 | 1337649 |
| 16 | 4847637 |
| 17 | 17680265 |
| 18 | 64823110 |
| 19 | 238824212 |
| 20 | 883634026 |