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 | 45 |
| 1 | 1485 |
| 2 | 22275 |
| 3 | 212355 |
| 4 | 1486485 |
| 5 | 8281845 |
| 6 | 38648610 |
| 7 | 156434850 |
| 8 | 563165460 |
| 9 | 1837398420 |
| 10 | 5512195260 |
| 11 | 15380181180 |
| 12 | 40281426900 |
| 13 | 99773995860 |
| 14 | 235181561670 |
| 15 | 530311364550 |
| 16 | 1149007956525 |
| 17 | 2401177618125 |
| 18 | 4855714738875 |
| 19 | 9528883810875 |
| 20 | 18191505457125 |