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 | 3 |
| 3 | 7 |
| 4 | 19 |
| 5 | 52 |
| 6 | 162 |
| 7 | 505 |
| 8 | 1666 |
| 9 | 5576 |
| 10 | 19135 |
| 11 | 66494 |
| 12 | 234316 |
| 13 | 833620 |
| 14 | 2992817 |
| 15 | 10822802 |
| 16 | 39395434 |
| 17 | 144207387 |
| 18 | 530534468 |
| 19 | 1960521470 |
| 20 | 7273963575 |
| 21 | 27085625086 |
| 22 | 101188629692 |
| 23 | 379160330195 |
| 24 | 1424634014730 |
| 25 | 5366319233160 |