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 | 3 |
| 2 | 30 |
| 3 | 70 |
| 4 | 315 |
| 5 | 693 |
| 6 | 12012 |
| 7 | 25740 |
| 8 | 109395 |
| 9 | 230945 |
| 10 | 1939938 |
| 11 | 4056234 |
| 12 | 16900975 |
| 13 | 35102025 |
| 14 | 1163381400 |
| 15 | 2404321560 |
| 16 | 9917826435 |
| 17 | 20419054425 |
| 18 | 167890003050 |
| 19 | 344616322050 |
| 20 | 1412926920405 |
| 21 | 2893136075115 |
| 22 | 47342226683700 |
| 23 | 96742811049300 |
| 24 | 395033145117975 |