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) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 11 |
| 7 | 30 |
| 8 | 96 |
| 9 | 339 |
| 10 | 1316 |
| 11 | 5584 |
| 12 | 25733 |
| 13 | 128025 |
| 14 | 683949 |
| 15 | 3905083 |
| 16 | 23731187 |
| 17 | 152934464 |
| 18 | 1041782238 |
| 19 | 7479469995 |
| 20 | 56448098958 |
| 21 | 446768591341 |
| 22 | 3700276748921 |
| 23 | 32007269639380 |
| 24 | 288630046441757 |
| 25 | 2708888570942365 |
| 26 | 26419890078249485 |
| 27 | 267389254029561667 |
| 28 | 2804508541393392135 |
| 29 | 30446382653772707171 |
| 30 | 341729529206733994569 |