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 | 2 |
| 2 | 7 |
| 3 | 31 |
| 4 | 174 |
| 5 | 1194 |
| 6 | 9729 |
| 7 | 91531 |
| 8 | 976635 |
| 9 | 11649919 |
| 10 | 153658286 |
| 11 | 2220622973 |
| 12 | 34897864282 |
| 13 | 592571575477 |
| 14 | 10812096348481 |
| 15 | 210974531531348 |
| 16 | 4384121200214696 |
| 17 | 96663164984512948 |
| 18 | 2253908578415276547 |
| 19 | 55415197638867035176 |
| 20 | 1432803507864157284463 |