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 | 510 |
| 2 | 18660 |
| 3 | 223290 |
| 4 | 1448520 |
| 5 | 6433590 |
| 6 | 22151340 |
| 7 | 63588210 |
| 8 | 159338640 |
| 9 | 359376750 |
| 10 | 745368180 |
| 11 | 1443884970 |
| 12 | 2642886360 |
| 13 | 4611828390 |
| 14 | 7725765180 |
| 15 | 12493804770 |
| 16 | 19592282400 |
| 17 | 29903014110 |
| 18 | 44556993540 |
| 19 | 64983894810 |
| 20 | 92967744360 |
| 21 | 130709124630 |
| 22 | 180894272460 |