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 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 15 |
| 5 | 114 |
| 6 | 1159 |
| 7 | 14838 |
| 8 | 229401 |
| 9 | 4159662 |
| 10 | 86580636 |
| 11 | 2034850425 |
| 12 | 53303009286 |
| 13 | 1539990513588 |
| 14 | 48648616439496 |
| 15 | 1668228105283302 |
| 16 | 61715049142446537 |
| 17 | 2450018515737072792 |
| 18 | 103892256368706869356 |
| 19 | 4686744256645813560957 |