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 | 2 |
| 3 | 3 |
| 4 | 9 |
| 5 | 20 |
| 6 | 64 |
| 7 | 205 |
| 8 | 747 |
| 9 | 2767 |
| 10 | 10850 |
| 11 | 43254 |
| 12 | 176990 |
| 13 | 735007 |
| 14 | 3099272 |
| 15 | 13220407 |
| 16 | 57001841 |
| 17 | 248009246 |
| 18 | 1087947441 |
| 19 | 4807232915 |
| 20 | 21381055533 |
| 21 | 95660032110 |
| 22 | 430298114499 |
| 23 | 1945096434552 |
| 24 | 8832200860663 |
| 25 | 40271358004756 |
| 26 | 184325394540531 |
| 27 | 846667179332120 |