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 | 3 |
| 2 | 33 |
| 3 | 141 |
| 4 | 3993 |
| 5 | 46264 |
| 6 | 999999 |
| 7 | 1736371 |
| 8 | 23911932 |
| 9 | 398989893 |
| 10 | 136776310 |
| 11 | 21348884312 |
| 12 | 450197791054 |
| 13 | 9475082805749 |
| 14 | 95715977951759 |
| 15 | 697763767367796 |
| 16 | 4855796336975584 |
| 17 | 42611063036011624 |
| 18 | 700015327723510007 |
| 19 | 5851405951595041585 |
| 20 | 74054579700797545047 |