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 | 5 |
| 3 | 18 |
| 4 | 63 |
| 5 | 218 |
| 6 | 891 |
| 7 | 3676 |
| 8 | 15137 |
| 9 | 60580 |
| 10 | 238672 |
| 11 | 953501 |
| 12 | 3826167 |
| 13 | 15308186 |
| 14 | 61204878 |
| 15 | 244709252 |
| 16 | 979285522 |
| 17 | 3917052950 |
| 18 | 15664274802 |
| 19 | 62663847447 |
| 20 | 250662444349 |
| 21 | 1002632090376 |
| 22 | 4010544455838 |
| 23 | 16042042419476 |
| 24 | 64168305037147 |
| 25 | 256675237863576 |