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 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 7 |
| 5 | 22 |
| 6 | 96 |
| 7 | 380 |
| 8 | 1853 |
| 9 | 8510 |
| 10 | 44940 |
| 11 | 229836 |
| 12 | 1296410 |
| 13 | 7211116 |
| 14 | 43096912 |
| 15 | 256874200 |
| 16 | 1617413773 |
| 17 | 10226972110 |
| 18 | 67542201972 |
| 19 | 449809389740 |
| 20 | 3104409032126 |