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 | 11 |
| 2 | 2047 |
| 3 | 88573 |
| 4 | 1398101 |
| 5 | 12207031 |
| 6 | 72559411 |
| 7 | 329554457 |
| 8 | 1227133513 |
| 9 | 3922632451 |
| 10 | 11111111111 |
| 11 | 28531167061 |
| 12 | 67546215517 |
| 13 | 149346699503 |
| 14 | 311505013051 |
| 15 | 617839704241 |
| 16 | 1172812402961 |
| 17 | 2141993519227 |
| 18 | 3780494710543 |
| 19 | 6471681049901 |
| 20 | 10778947368421 |
| 21 | 17513875027111 |
| 22 | 27824681019587 |