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 | 5 |
| 4 | 14 |
| 5 | 42 |
| 6 | 132 |
| 7 | 426 |
| 8 | 1390 |
| 9 | 4544 |
| 10 | 14822 |
| 11 | 48183 |
| 12 | 156118 |
| 13 | 504487 |
| 14 | 1627000 |
| 15 | 5240019 |
| 16 | 16861453 |
| 17 | 54228190 |
| 18 | 174351450 |
| 19 | 560481708 |
| 20 | 1801653769 |
| 21 | 5791301311 |
| 22 | 18615976402 |
| 23 | 59841686254 |
| 24 | 192366897839 |
| 25 | 618392292337 |