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 | 5 |
| 2 | 19 |
| 3 | 58 |
| 4 | 168 |
| 5 | 488 |
| 6 | 1422 |
| 7 | 4160 |
| 8 | 12214 |
| 9 | 35960 |
| 10 | 106072 |
| 11 | 313246 |
| 12 | 925694 |
| 13 | 2736638 |
| 14 | 8092056 |
| 15 | 23930330 |
| 16 | 70772252 |
| 17 | 209309684 |
| 18 | 619043562 |
| 19 | 1830861726 |
| 20 | 5414905178 |
| 21 | 16014983408 |
| 22 | 47365507554 |
| 23 | 140087012360 |
| 24 | 414317718488 |
| 25 | 1225375238694 |