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 | 2 |
| 3 | 6 |
| 4 | 30 |
| 5 | 5 |
| 6 | 35 |
| 7 | 70 |
| 8 | 770 |
| 9 | 10010 |
| 10 | 5005 |
| 11 | 15015 |
| 12 | 255255 |
| 13 | 4849845 |
| 14 | 1616615 |
| 15 | 3233230 |
| 16 | 74364290 |
| 17 | 37182145 |
| 18 | 1078282205 |
| 19 | 6469693230 |
| 20 | 200560490130 |
| 21 | 6077590610 |
| 22 | 3038795305 |
| 23 | 607759061 |
| 24 | 22487085257 |
| 25 | 44974170514 |
| 26 | 134922511542 |
| 27 | 5531822973222 |
| 28 | 921970495537 |
| 29 | 39644731308091 |