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 | 13 |
| 2 | 60 |
| 3 | 337 |
| 4 | 1880 |
| 5 | 10290 |
| 6 | 56955 |
| 7 | 314044 |
| 8 | 1732883 |
| 9 | 9562608 |
| 10 | 52762665 |
| 11 | 291142893 |
| 12 | 1606482609 |
| 13 | 8864368984 |
| 14 | 48912478517 |
| 15 | 269892775507 |
| 16 | 1489234149184 |
| 17 | 8217404544373 |
| 18 | 45342593611494 |
| 19 | 250194667755280 |
| 20 | 1380542367891973 |