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 | 5 |
| 3 | 9 |
| 4 | 19 |
| 5 | 41 |
| 6 | 87 |
| 7 | 187 |
| 8 | 425 |
| 9 | 1041 |
| 10 | 2689 |
| 11 | 7031 |
| 12 | 18015 |
| 13 | 44503 |
| 14 | 105503 |
| 15 | 240267 |
| 16 | 527035 |
| 17 | 1116023 |
| 18 | 2283321 |
| 19 | 4509661 |
| 20 | 8574251 |
| 21 | 15613035 |
| 22 | 26989459 |
| 23 | 43596473 |
| 24 | 63714861 |
| 25 | 77517775 |
| 26 | 54160583 |
| 27 | -87072621 |
| 28 | -539390369 |
| 29 | -1742001769 |
| 30 | -4661299497 |