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 | 2 |
| 3 | 5 |
| 4 | 12 |
| 5 | 30 |
| 6 | 77 |
| 7 | 201 |
| 8 | 532 |
| 9 | 1427 |
| 10 | 3868 |
| 11 | 10579 |
| 12 | 29161 |
| 13 | 80931 |
| 14 | 225954 |
| 15 | 634197 |
| 16 | 1788453 |
| 17 | 5064877 |
| 18 | 14398536 |
| 19 | 41074364 |
| 20 | 117541744 |
| 21 | 337337862 |
| 22 | 970704394 |
| 23 | 2800059428 |
| 24 | 8095161902 |
| 25 | 23452565124 |
| 26 | 68076579332 |
| 27 | 197965830430 |