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 | 2 |
| 2 | 6 |
| 3 | 26 |
| 4 | 91 |
| 5 | 424 |
| 6 | 1563 |
| 7 | 7490 |
| 8 | 28363 |
| 9 | 138154 |
| 10 | 532277 |
| 11 | 2622108 |
| 12 | 10229514 |
| 13 | 50827494 |
| 14 | 200236656 |
| 15 | 1001864238 |
| 16 | 3978724091 |
| 17 | 20024629606 |
| 18 | 80072228433 |
| 19 | 405071776024 |
| 20 | 1629554359654 |
| 21 | 8281491341260 |
| 22 | 33495987519034 |
| 23 | 170937706521070 |
| 24 | 694795683685757 |
| 25 | 3559265886170942 |