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 | 0 |
| 1 | 1 |
| 2 | 9 |
| 3 | 62 |
| 4 | 387 |
| 5 | 2305 |
| 6 | 13392 |
| 7 | 76733 |
| 8 | 436149 |
| 9 | 2467414 |
| 10 | 13919895 |
| 11 | 78398189 |
| 12 | 441105696 |
| 13 | 2480385673 |
| 14 | 13942462833 |
| 15 | 78354837710 |
| 16 | 440286745563 |
| 17 | 2473838793577 |
| 18 | 13899100976496 |
| 19 | 78088971710501 |
| 20 | 438717826841085 |