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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 225 |
| 6 | 2304 |
| 7 | 12916 |
| 8 | 52480 |
| 9 | 172810 |
| 10 | 489280 |
| 11 | 1234948 |
| 12 | 2846272 |
| 13 | 6092515 |
| 14 | 12263680 |
| 15 | 23434840 |
| 16 | 42828032 |
| 17 | 75296468 |
| 18 | 127959680 |
| 19 | 211022360 |
| 20 | 338814080 |
| 21 | 531091781 |
| 22 | 814651904 |
| 23 | 1225304300 |
| 24 | 1810265600 |
| 25 | 2631035550 |
| 26 | 3766825920 |
| 27 | 5318617980 |
| 28 | 7413931200 |
| 29 | 10212392775 |
| 30 | 13912204800 |
| 31 | 18757613424 |
| 32 | 25047492096 |
| 33 | 33145159080 |
| 34 | 43489557760 |
| 35 | 56607936880 |
| 36 | 73130176768 |
| 37 | 93804916777 |
| 38 | 119517648640 |
| 39 | 151310950180 |
| 40 | 190407043840 |