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 | 3 |
| 2 | 9 |
| 3 | 29 |
| 4 | 98 |
| 5 | 342 |
| 6 | 1221 |
| 7 | 4433 |
| 8 | 16302 |
| 9 | 60554 |
| 10 | 226746 |
| 11 | 854658 |
| 12 | 3239044 |
| 13 | 12332140 |
| 14 | 47137005 |
| 15 | 180780345 |
| 16 | 695367510 |
| 17 | 2681600130 |
| 18 | 10364759790 |
| 19 | 40142121030 |
| 20 | 155748675420 |
| 21 | 605274171060 |
| 22 | 2355676013730 |
| 23 | 9180275261274 |
| 24 | 35819645937228 |