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 | 3 |
| 3 | 19 |
| 4 | 175 |
| 5 | 2101 |
| 6 | 31031 |
| 7 | 543607 |
| 8 | 11012415 |
| 9 | 253202761 |
| 10 | 6513215599 |
| 11 | 185311670611 |
| 12 | 5777672071535 |
| 13 | 195881901213181 |
| 14 | 7174630439858727 |
| 15 | 282325794823047151 |
| 16 | 11878335717996660991 |
| 17 | 532092356706983938321 |
| 18 | 25283323623228812584415 |
| 19 | 1270184310304975912766347 |