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 | 2 |
| 2 | 7 |
| 3 | 23 |
| 4 | 75 |
| 5 | 242 |
| 6 | 772 |
| 7 | 2430 |
| 8 | 7529 |
| 9 | 22941 |
| 10 | 68801 |
| 11 | 203488 |
| 12 | 594994 |
| 13 | 1724242 |
| 14 | 4963041 |
| 15 | 14213111 |
| 16 | 40540661 |
| 17 | 115235882 |
| 18 | 326470662 |
| 19 | 921780312 |
| 20 | 2593408123 |
| 21 | 7269728291 |
| 22 | 20302519239 |
| 23 | 56493171410 |
| 24 | 156652350614 |
| 25 | 433009258768 |