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 | 7 |
| 3 | 9 |
| 4 | 43 |
| 5 | 52 |
| 6 | 303 |
| 7 | 355 |
| 8 | 658 |
| 9 | 4303 |
| 10 | 9264 |
| 11 | 50623 |
| 12 | 414248 |
| 13 | 1293367 |
| 14 | 4294349 |
| 15 | 18470763 |
| 16 | 41235875 |
| 17 | 265886013 |
| 18 | 1104779927 |
| 19 | 4685005721 |
| 20 | 5789785648 |
| 21 | 22054362665 |
| 22 | 49898510978 |
| 23 | 171749895599 |
| 24 | 736898093374 |
| 25 | 908647988973 |
| 26 | 4371490049266 |
| 27 | 40252058432367 |