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) |
|---|---|
| 0 | 1 |
| 1 | 9 |
| 2 | 511 |
| 3 | 9841 |
| 4 | 87381 |
| 5 | 488281 |
| 6 | 2015539 |
| 7 | 6725601 |
| 8 | 19173961 |
| 9 | 48427561 |
| 10 | 111111111 |
| 11 | 235794769 |
| 12 | 469070941 |
| 13 | 883708281 |
| 14 | 1589311291 |
| 15 | 2745954241 |
| 16 | 4581298449 |
| 17 | 7411742281 |
| 18 | 11668193551 |
| 19 | 17927094321 |
| 20 | 26947368421 |
| 21 | 39714002329 |
| 22 | 57489010371 |
| 23 | 81870575521 |
| 24 | 114861197401 |