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 | 7 |
| 2 | 104 |
| 3 | 1748 |
| 4 | 31000 |
| 5 | 566618 |
| 6 | 10559208 |
| 7 | 199448964 |
| 8 | 3804949176 |
| 9 | 73143988775 |
| 10 | 1414591812920 |
| 11 | 27492340515912 |
| 12 | 536480138597624 |
| 13 | 10504551860174120 |
| 14 | 206284010045343000 |
| 15 | 4061109502392133464 |
| 16 | 80126310234711780600 |
| 17 | 1583953257985260802200 |
| 18 | 31365436013686385802048 |