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 | 1 |
| 3 | 7 |
| 4 | 13 |
| 5 | 112 |
| 6 | 247 |
| 7 | 2310 |
| 8 | 5525 |
| 9 | 53998 |
| 10 | 135408 |
| 11 | 1360289 |
| 12 | 3518515 |
| 13 | 36017352 |
| 14 | 95223414 |
| 15 | 988172368 |
| 16 | 2655417765 |
| 17 | 27844071255 |
| 18 | 75769712590 |
| 19 | 801012669457 |
| 20 | 2201663313200 |
| 21 | 23428926096576 |
| 22 | 64924369564353 |
| 23 | 694644371065372 |
| 24 | 1938034271677595 |
| 25 | 20829931845958872 |
| 26 | 58448142042957576 |