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 | 9 |
| 2 | 49 |
| 3 | 179 |
| 4 | 711 |
| 5 | 2390 |
| 6 | 8361 |
| 7 | 27082 |
| 8 | 89389 |
| 9 | 283170 |
| 10 | 905307 |
| 11 | 2825245 |
| 12 | 8854116 |
| 13 | 27341969 |
| 14 | 84550769 |
| 15 | 259046260 |
| 16 | 793589833 |
| 17 | 2416512240 |
| 18 | 7352490113 |
| 19 | 22279068811 |
| 20 | 67435591018 |
| 21 | 203525629398 |
| 22 | 613550161717 |
| 23 | 1845654390776 |
| 24 | 5545861291941 |
| 25 | 16637001197044 |
| 26 | 49858191850323 |