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 | 1 |
| 3 | 9 |
| 4 | 13 |
| 5 | 61 |
| 6 | 117 |
| 7 | 421 |
| 8 | 949 |
| 9 | 2997 |
| 10 | 7381 |
| 11 | 21781 |
| 12 | 56277 |
| 13 | 160213 |
| 14 | 424789 |
| 15 | 1186389 |
| 16 | 3189589 |
| 17 | 8817493 |
| 18 | 23883093 |
| 19 | 65663317 |
| 20 | 178568533 |
| 21 | 489512277 |
| 22 | 1334064469 |
| 23 | 3651347797 |
| 24 | 9962435925 |
| 25 | 27244344661 |
| 26 | 74380006741 |
| 27 | 203315811669 |
| 28 | 555257419093 |
| 29 | 1517414896981 |
| 30 | 4144807761237 |