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 | 0 |
| 1 | 1 |
| 2 | 7 |
| 3 | 42 |
| 4 | 242 |
| 5 | 1375 |
| 6 | 7773 |
| 7 | 43876 |
| 8 | 247684 |
| 9 | 1399293 |
| 10 | 7913955 |
| 11 | 44812878 |
| 12 | 254064726 |
| 13 | 1442131899 |
| 14 | 8195232633 |
| 15 | 46621424520 |
| 16 | 265490365448 |
| 17 | 1513290869881 |
| 18 | 8633347134975 |
| 19 | 49293941140402 |
| 20 | 281670686307130 |