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 | 2 |
| 3 | 10 |
| 4 | 72 |
| 5 | 701 |
| 6 | 8658 |
| 7 | 129949 |
| 8 | 2298912 |
| 9 | 46866034 |
| 10 | 1082120050 |
| 11 | 27916772489 |
| 12 | 795910114440 |
| 13 | 24851643870041 |
| 14 | 843458630403298 |
| 15 | 30918112619119426 |
| 16 | 1217359297034666112 |
| 17 | 51240457936070359069 |
| 18 | 2296067756927144738850 |
| 19 | 109127748348241605689981 |