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 | 5 |
| 2 | 17 |
| 3 | 45 |
| 4 | 96 |
| 5 | 155 |
| 6 | 119 |
| 7 | -365 |
| 8 | -2217 |
| 9 | -7360 |
| 10 | -18791 |
| 11 | -38435 |
| 12 | -57639 |
| 13 | -28875 |
| 14 | 200992 |
| 15 | 1015075 |
| 16 | 3179711 |
| 17 | 7796715 |
| 18 | 15240559 |
| 19 | 20915840 |
| 20 | 3218033 |
| 21 | -103746315 |
| 22 | -458355231 |
| 23 | -1362884995 |
| 24 | -3211177504 |
| 25 | -5977952405 |
| 26 | -7345234233 |
| 27 | 2382397955 |
| 28 | 51340513351 |
| 29 | 204512766400 |
| 30 | 579756435849 |