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 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 304 |
| 5 | 10741 |
| 6 | 127960 |
| 7 | 870589 |
| 8 | 4197456 |
| 9 | 16005187 |
| 10 | 51439096 |
| 11 | 145085447 |
| 12 | 369074128 |
| 13 | 863338777 |
| 14 | 1883786680 |
| 15 | 3875953561 |
| 16 | 7583888944 |
| 17 | 14206566327 |
| 18 | 25617069208 |
| 19 | 44663199283 |
| 20 | 75572017136 |
| 21 | 124485188701 |
| 22 | 200156902936 |
| 23 | 314851577749 |
| 24 | 485484612496 |
| 25 | 735056106571 |
| 26 | 1094434774968 |