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 | 125 |
| 5 | 1141 |
| 6 | 12943 |
| 7 | 182743 |
| 8 | 3080025 |
| 9 | 60530761 |
| 10 | 1357997531 |
| 11 | 34237329611 |
| 12 | 957927505717 |
| 13 | 29446189175677 |
| 14 | 986272776455415 |
| 15 | 35746439978786671 |
| 16 | 1393753996031259953 |
| 17 | 58165330912030118161 |
| 18 | 2586788074128361802419 |