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 | 3 |
| 3 | 8 |
| 4 | 22 |
| 5 | 58 |
| 6 | 158 |
| 7 | 426 |
| 8 | 1170 |
| 9 | 3224 |
| 10 | 8977 |
| 11 | 25105 |
| 12 | 70680 |
| 13 | 199739 |
| 14 | 566842 |
| 15 | 1613454 |
| 16 | 4605788 |
| 17 | 13177776 |
| 18 | 37782903 |
| 19 | 108522417 |
| 20 | 312207970 |
| 21 | 899460505 |
| 22 | 2594638480 |
| 23 | 7493254511 |
| 24 | 21663019843 |
| 25 | 62687523055 |
| 26 | 181561095507 |
| 27 | 526275453283 |
| 28 | 1526600618192 |
| 29 | 4431347014046 |
| 30 | 12516888508178 |