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 | 1 |
| 2 | 5 |
| 3 | 22 |
| 4 | 164 |
| 5 | 1030 |
| 6 | 8885 |
| 7 | 65954 |
| 8 | 614404 |
| 9 | 5030004 |
| 10 | 49145460 |
| 11 | 429166584 |
| 12 | 4331674512 |
| 13 | 39599553708 |
| 14 | 409230997461 |
| 15 | 3871362876810 |
| 16 | 40730958917220 |
| 17 | 395684757649324 |
| 18 | 4222043580320852 |
| 19 | 41894315105061848 |
| 20 | 452123832420881296 |