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 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 39 |
| 4 | 381 |
| 5 | 4284 |
| 6 | 53163 |
| 7 | 710810 |
| 8 | 10085621 |
| 9 | 150326044 |
| 10 | 2336828792 |
| 11 | 37687170215 |
| 12 | 628069684439 |
| 13 | 10782885724300 |
| 14 | 190248852445782 |
| 15 | 3442896376032300 |
| 16 | 63804661588968521 |
| 17 | 1209314277690837796 |