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 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 2 |
| 7 | 14 |
| 8 | 98 |
| 9 | 546 |
| 10 | 2562 |
| 11 | 10626 |
| 12 | 41118 |
| 13 | 174174 |
| 14 | 1093092 |
| 15 | 10005996 |
| 16 | 98041944 |
| 17 | 889104216 |
| 18 | 7315812504 |
| 19 | 55893493656 |
| 20 | 421564046904 |
| 21 | 3519008733240 |
| 22 | 36011379484080 |
| 23 | 435775334314320 |
| 24 | 5538098453968080 |
| 25 | 68428271204813520 |
| 26 | 805379194188288720 |