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 | 4 |
| 3 | 16 |
| 4 | 58 |
| 5 | 624 |
| 6 | 1520 |
| 7 | 8346 |
| 8 | 9317 |
| 9 | 31221 |
| 10 | 240048 |
| 11 | 297624 |
| 12 | 778144 |
| 13 | 2757880 |
| 14 | 4670769 |
| 15 | 7654224 |
| 16 | 24206384 |
| 17 | 54806653 |
| 18 | 76521364 |
| 19 | 260393208 |
| 20 | 846807152 |
| 21 | 19488644316 |
| 22 | 58671741024 |
| 23 | 105968380189 |
| 24 | 140689013614 |
| 25 | 325374626148 |
| 26 | 535755688021 |
| 27 | 1404720439053 |
| 28 | 3116427665348 |
| 29 | 3883018238329 |
| 30 | 16166305650060 |