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 | 2 |
| 3 | 5 |
| 4 | 16 |
| 5 | 56 |
| 6 | 217 |
| 7 | 876 |
| 8 | 3686 |
| 9 | 15903 |
| 10 | 70103 |
| 11 | 314042 |
| 12 | 1426076 |
| 13 | 6548060 |
| 14 | 30352695 |
| 15 | 141837086 |
| 16 | 667469159 |
| 17 | 3160370217 |
| 18 | 15045244375 |
| 19 | 71970393570 |
| 20 | 345766441537 |
| 21 | 1667629158127 |
| 22 | 8071308125136 |
| 23 | 39190243658297 |
| 24 | 190845259909328 |
| 25 | 931856232714004 |
| 26 | 4561292365652751 |