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 | 7 |
| 2 | 41 |
| 3 | 223 |
| 4 | 1169 |
| 5 | 6007 |
| 6 | 30521 |
| 7 | 154063 |
| 8 | 774689 |
| 9 | 3886567 |
| 10 | 19472201 |
| 11 | 97479103 |
| 12 | 487749809 |
| 13 | 2439811927 |
| 14 | 12202248281 |
| 15 | 61020807343 |
| 16 | 305132734529 |
| 17 | 1525749766087 |
| 18 | 7629007110761 |
| 19 | 38145810394783 |
| 20 | 190731376496849 |