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 | 7 |
| 3 | 19 |
| 4 | 91 |
| 5 | 331 |
| 6 | 1387 |
| 7 | 5419 |
| 8 | 21931 |
| 9 | 87211 |
| 10 | 349867 |
| 11 | 1397419 |
| 12 | 5593771 |
| 13 | 22366891 |
| 14 | 89483947 |
| 15 | 357903019 |
| 16 | 1431677611 |
| 17 | 5726579371 |
| 18 | 22906579627 |
| 19 | 91625794219 |
| 20 | 366504225451 |
| 21 | 1466014804651 |
| 22 | 5864063412907 |
| 23 | 23456245263019 |
| 24 | 93824997829291 |
| 25 | 375299957762731 |