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 | 1 |
| 3 | 3 |
| 4 | 7 |
| 5 | 22 |
| 6 | 67 |
| 7 | 225 |
| 8 | 765 |
| 9 | 2704 |
| 10 | 9710 |
| 11 | 35558 |
| 12 | 131859 |
| 13 | 494892 |
| 14 | 1874901 |
| 15 | 7162807 |
| 16 | 27558511 |
| 17 | 106695148 |
| 18 | 415346144 |
| 19 | 1624780952 |
| 20 | 6383671910 |
| 21 | 25179642120 |
| 22 | 99670897534 |
| 23 | 395810459602 |
| 24 | 1576464630375 |
| 25 | 6295827843098 |