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 | 30 |
| 2 | 250 |
| 3 | 1650 |
| 4 | 12770 |
| 5 | 100230 |
| 6 | 805906 |
| 7 | 6566814 |
| 8 | 54086114 |
| 9 | 449108706 |
| 10 | 3753661210 |
| 11 | 31540650842 |
| 12 | 266200099346 |
| 13 | 2255103585986 |
| 14 | 19164991781962 |
| 15 | 163321999341570 |
| 16 | 1395146780098946 |
| 17 | 11942807195629546 |
| 18 | 102422953911204100 |