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 | 3 |
| 3 | 6 |
| 4 | 19 |
| 5 | 51 |
| 6 | 114 |
| 7 | 312 |
| 8 | 981 |
| 9 | 2616 |
| 10 | 6564 |
| 11 | 19647 |
| 12 | 59922 |
| 13 | 159056 |
| 14 | 430302 |
| 15 | 1329996 |
| 16 | 3926217 |
| 17 | 10498968 |
| 18 | 30052851 |
| 19 | 93244764 |
| 20 | 267690168 |
| 21 | 729649143 |
| 22 | 2173840338 |
| 23 | 6663260223 |
| 24 | 18768583674 |
| 25 | 52570016676 |
| 26 | 160362713250 |
| 27 | 481809941520 |
| 28 | 1346473504182 |
| 29 | 3886164785178 |