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 | 3 |
| 1 | 17 |
| 2 | 121 |
| 3 | 953 |
| 4 | 7873 |
| 5 | 66857 |
| 6 | 578161 |
| 7 | 5063033 |
| 8 | 44726593 |
| 9 | 397498697 |
| 10 | 3547251601 |
| 11 | 31743858713 |
| 12 | 284606322913 |
| 13 | 2554926530537 |
| 14 | 22955156635441 |
| 15 | 206361317111993 |
| 16 | 1855841298824833 |
| 17 | 16694108359242377 |
| 18 | 150196195253929681 |