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 | 7 |
| 3 | 41 |
| 4 | 349 |
| 5 | 3539 |
| 6 | 42451 |
| 7 | 585605 |
| 8 | 9130297 |
| 9 | 158692679 |
| 10 | 3041499871 |
| 11 | 63712004729 |
| 12 | 1447946191957 |
| 13 | 35479218963083 |
| 14 | 932326476195115 |
| 15 | 26153289728300909 |
| 16 | 779995883104560241 |
| 17 | 24644267406802467215 |
| 18 | 822278654588440803511 |
| 19 | 28891372907012629446881 |