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 | 23 |
| 2 | 299 |
| 3 | 2898 |
| 4 | 23184 |
| 5 | 161253 |
| 6 | 1006250 |
| 7 | 5751679 |
| 8 | 30558053 |
| 9 | 152543797 |
| 10 | 721432513 |
| 11 | 3253563394 |
| 12 | 14065808815 |
| 13 | 58544010641 |
| 14 | 235435351628 |
| 15 | 917591584210 |
| 16 | 3474891526923 |
| 17 | 12815003028813 |
| 18 | 46113476682975 |