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 | 0 |
| 1 | 1 |
| 2 | 8 |
| 3 | 107 |
| 4 | 1760 |
| 5 | 32298 |
| 6 | 634128 |
| 7 | 13034247 |
| 8 | 276943568 |
| 9 | 6033834950 |
| 10 | 134069957840 |
| 11 | 3026476515790 |
| 12 | 69213144181888 |
| 13 | 1600157697995092 |
| 14 | 37337615574348960 |
| 15 | 878166685063548639 |
| 16 | 20797051344280763184 |
| 17 | 495509950454603339310 |
| 18 | 11869278747340342255440 |
| 19 | 285669061791469915886250 |
| 20 | 6904850429493240677872320 |