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 | 2 |
| 3 | 12 |
| 4 | 22 |
| 5 | 124 |
| 6 | 276 |
| 7 | 1496 |
| 8 | 3686 |
| 9 | 19436 |
| 10 | 51068 |
| 11 | 263720 |
| 12 | 724860 |
| 13 | 3681880 |
| 14 | 10466920 |
| 15 | 52450992 |
| 16 | 153093254 |
| 17 | 758495564 |
| 18 | 2261603564 |
| 19 | 11096526344 |
| 20 | 33676743956 |
| 21 | 163842737928 |
| 22 | 504738342808 |
| 23 | 2437418983888 |
| 24 | 7605947276508 |
| 25 | 36487283224952 |
| 26 | 115140704639576 |