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 | 7 |
| 2 | 63 |
| 3 | 574 |
| 4 | 5365 |
| 5 | 49894 |
| 6 | 448649 |
| 7 | 3825307 |
| 8 | 30555624 |
| 9 | 227542455 |
| 10 | 1579153474 |
| 11 | 10236107278 |
| 12 | 62184207773 |
| 13 | 355425984636 |
| 14 | 1918894455423 |
| 15 | 9822580592133 |
| 16 | 47841257692021 |
| 17 | 222427734697477 |
| 18 | 990076818618586 |