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 | 30 |
| 3 | 198 |
| 4 | 1326 |
| 5 | 8886 |
| 6 | 59550 |
| 7 | 399078 |
| 8 | 2674446 |
| 9 | 17922966 |
| 10 | 120111870 |
| 11 | 804937158 |
| 12 | 5394336366 |
| 13 | 36150480246 |
| 14 | 242264688990 |
| 15 | 1623551862438 |
| 16 | 10880333659086 |
| 17 | 72915231888726 |
| 18 | 488645955902910 |
| 19 | 3274691227542918 |
| 20 | 21945546680994606 |
| 21 | 147069444311876406 |
| 22 | 985595016821145630 |