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 | 7 |
| 3 | 40 |
| 4 | 202 |
| 5 | 1215 |
| 6 | 8143 |
| 7 | 58621 |
| 8 | 440257 |
| 9 | 3424679 |
| 10 | 27409998 |
| 11 | 224373160 |
| 12 | 1870585458 |
| 13 | 15834656002 |
| 14 | 135779962759 |
| 15 | 1177207270203 |
| 16 | 10304191320776 |
| 17 | 90948823579814 |
| 18 | 808675898548205 |