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 | 27 |
| 4 | 109 |
| 5 | 453 |
| 6 | 1922 |
| 7 | 8284 |
| 8 | 36155 |
| 9 | 159435 |
| 10 | 709246 |
| 11 | 3178992 |
| 12 | 14343567 |
| 13 | 65099245 |
| 14 | 297015765 |
| 15 | 1361584755 |
| 16 | 6268757195 |
| 17 | 28975155915 |
| 18 | 134410918700 |
| 19 | 625578384150 |
| 20 | 2920488902795 |
| 21 | 13672762887465 |
| 22 | 64179220019365 |
| 23 | 301987822527627 |