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 | 4 |
| 3 | 16 |
| 4 | 71 |
| 5 | 322 |
| 6 | 1455 |
| 7 | 6558 |
| 8 | 29548 |
| 9 | 133146 |
| 10 | 599998 |
| 11 | 2703794 |
| 12 | 12184181 |
| 13 | 54905857 |
| 14 | 247423522 |
| 15 | 1114970351 |
| 16 | 5024416818 |
| 17 | 22641646338 |
| 18 | 102030577247 |
| 19 | 459782762029 |
| 20 | 2071929748572 |
| 21 | 9336785189996 |
| 22 | 42074572144477 |
| 23 | 189601622519548 |
| 24 | 854406199035948 |
| 25 | 3850230516227419 |