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 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 6 |
| 6 | 19 |
| 7 | 60 |
| 8 | 193 |
| 9 | 636 |
| 10 | 2141 |
| 11 | 7331 |
| 12 | 25451 |
| 13 | 89385 |
| 14 | 317036 |
| 15 | 1134100 |
| 16 | 4087104 |
| 17 | 14825482 |
| 18 | 54088470 |
| 19 | 198348985 |
| 20 | 730723956 |
| 21 | 2703194553 |
| 22 | 10037648254 |
| 23 | 37399878530 |
| 24 | 139785998185 |
| 25 | 523962161491 |
| 26 | 1969154471389 |
| 27 | 7418488063284 |
| 28 | 28010998254007 |
| 29 | 105986233046356 |
| 30 | 401804972780552 |