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) |
|---|---|
| 2 | 1 |
| 3 | 23 |
| 4 | 252 |
| 5 | 1666 |
| 6 | 7509 |
| 7 | 26865 |
| 8 | 79920 |
| 9 | 209096 |
| 10 | 491425 |
| 11 | 1064575 |
| 12 | 2150076 |
| 13 | 4104738 |
| 14 | 7458437 |
| 15 | 13005041 |
| 16 | 21857984 |
| 17 | 35598880 |
| 18 | 56353185 |
| 19 | 87019191 |
| 20 | 131364700 |
| 21 | 194364050 |
| 22 | 282314901 |
| 23 | 403316353 |
| 24 | 567402672 |
| 25 | 787201416 |
| 26 | 1078078209 |
| 27 | 1459020095 |
| 28 | 1952782300 |
| 29 | 2587048786 |
| 30 | 3394568325 |