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 | 1 |
| 3 | 4 |
| 4 | 5 |
| 5 | 16 |
| 6 | 82 |
| 7 | 169 |
| 8 | 541 |
| 9 | 2272 |
| 10 | 17965 |
| 11 | 44407 |
| 12 | 201751 |
| 13 | 801515 |
| 14 | 4890886 |
| 15 | 52218595 |
| 16 | 165519640 |
| 17 | 835947970 |
| 18 | 4290442728 |
| 19 | 24096524166 |
| 20 | 179566203960 |
| 21 | 2739764737710 |
| 22 | 9938147178960 |
| 23 | 60997160143920 |
| 24 | 331360222255920 |
| 25 | 2154105076695000 |