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 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 12 |
| 5 | 22 |
| 6 | 37 |
| 7 | 56 |
| 8 | 73 |
| 9 | 75 |
| 10 | 44 |
| 11 | -21 |
| 12 | -39 |
| 13 | 297 |
| 14 | 1751 |
| 15 | 5749 |
| 16 | 14104 |
| 17 | 27136 |
| 18 | 38163 |
| 19 | 22135 |
| 20 | -80421 |
| 21 | -369611 |
| 22 | -934754 |
| 23 | -1637758 |
| 24 | -1559395 |
| 25 | 2019629 |
| 26 | 14766699 |
| 27 | 44732254 |
| 28 | 94865112 |
| 29 | 138114302 |
| 30 | 61077521 |