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 | 0 |
| 1 | 0 |
| 2 | 2 |
| 3 | 43 |
| 4 | 276 |
| 5 | 1150 |
| 6 | 3710 |
| 7 | 10017 |
| 8 | 23688 |
| 9 | 50556 |
| 10 | 99450 |
| 11 | 183095 |
| 12 | 319132 |
| 13 | 531258 |
| 14 | 850486 |
| 15 | 1316525 |
| 16 | 1979280 |
| 17 | 2900472 |
| 18 | 4155378 |
| 19 | 5834691 |
| 20 | 8046500 |
| 21 | 10918390 |
| 22 | 14599662 |
| 23 | 19263673 |
| 24 | 25110296 |
| 25 | 32368500 |
| 26 | 41299050 |
| 27 | 52197327 |
| 28 | 65396268 |
| 29 | 81269426 |
| 30 | 100234150 |