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) |
|---|---|
| 1 | 20 |
| 2 | 400 |
| 3 | 4739 |
| 4 | 38561 |
| 5 | 242114 |
| 6 | 1253770 |
| 7 | 5588411 |
| 8 | 22075529 |
| 9 | 78911656 |
| 10 | 259222964 |
| 11 | 791787532 |
| 12 | 2269535600 |
| 13 | 6149706181 |
| 14 | 15847969147 |
| 15 | 39036356744 |
| 16 | 92295124070 |
| 17 | 210220319550 |
| 18 | 462719488690 |
| 19 | 986952548003 |
| 20 | 2044823738533 |
| 21 | 4124042889158 |