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 | 248 |
| 2 | 4124 |
| 3 | 34752 |
| 4 | 213126 |
| 5 | 1057504 |
| 6 | 4530744 |
| 7 | 17333248 |
| 8 | 60655377 |
| 9 | 197230000 |
| 10 | 603096260 |
| 11 | 1749556736 |
| 12 | 4848776870 |
| 13 | 12908659008 |
| 14 | 33161242504 |
| 15 | 82505707520 |
| 16 | 199429765972 |
| 17 | 469556091240 |
| 18 | 1079330385764 |
| 19 | 2426800117504 |
| 20 | 5346409013164 |