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 | 5 |
| 2 | 10 |
| 3 | 30 |
| 4 | 105 |
| 5 | 372 |
| 6 | 1460 |
| 7 | 5890 |
| 8 | 25275 |
| 9 | 110050 |
| 10 | 492744 |
| 11 | 2227270 |
| 12 | 10195070 |
| 13 | 46989180 |
| 14 | 218096780 |
| 15 | 1017447736 |
| 16 | 4768944375 |
| 17 | 22440372240 |
| 18 | 105966686200 |
| 19 | 501938733550 |
| 20 | 2384200190580 |
| 21 | 11353290083380 |