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 | 10 |
| 4 | 56 |
| 5 | 136 |
| 6 | 1952 |
| 7 | 5104 |
| 8 | 94208 |
| 9 | 605056 |
| 10 | 7741952 |
| 11 | 39917824 |
| 12 | 1458295808 |
| 13 | 6227024896 |
| 14 | 175463616512 |
| 15 | 2353813878784 |
| 16 | 48886264659968 |
| 17 | 355687428161536 |
| 18 | 17362063156969472 |
| 19 | 121645100409094144 |
| 20 | 6001501553433509888 |
| 21 | 85800344155030552576 |
| 22 | 2248030289949388439552 |