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 | 8953 |
| 2 | 856945 |
| 3 | 17538157 |
| 4 | 167729959 |
| 5 | 1018872811 |
| 6 | 4577127763 |
| 7 | 16581420835 |
| 8 | 51125645317 |
| 9 | 139071924069 |
| 10 | 342237634221 |
| 11 | 775938666273 |
| 12 | 1643151128475 |
| 13 | 3284313415527 |
| 14 | 6247630238079 |
| 15 | 11385659856231 |
| 16 | 19984965376233 |
| 17 | 33936690554865 |
| 18 | 55957080110537 |
| 19 | 89868204063989 |
| 20 | 140950465124591 |