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 | 0 |
| 2 | 1 |
| 3 | 15 |
| 4 | 106 |
| 5 | 821 |
| 6 | 6909 |
| 7 | 58683 |
| 8 | 509654 |
| 9 | 4508611 |
| 10 | 40421003 |
| 11 | 366300162 |
| 12 | 3348975103 |
| 13 | 30845805300 |
| 14 | 285887726304 |
| 15 | 2663962455651 |
| 16 | 24939375901980 |