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 | 117 |
| 3 | 1972 |
| 4 | 19750 |
| 5 | 150085 |
| 6 | 955347 |
| 7 | 5355983 |
| 8 | 27218249 |
| 9 | 127644118 |
| 10 | 559023840 |
| 11 | 2305566900 |
| 12 | 9009824325 |
| 13 | 33520023813 |
| 14 | 119176965881 |
| 15 | 406212717567 |
| 16 | 1330964850429 |
| 17 | 4202125841615 |
| 18 | 12811256626245 |
| 19 | 37790376053439 |