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 | 64 |
| 3 | 400 |
| 4 | 4624 |
| 5 | 26244 |
| 6 | 228484 |
| 7 | 2022084 |
| 8 | 20268004 |
| 9 | 202208400 |
| 10 | 2006860804 |
| 11 | 20220840000 |
| 12 | 200084446864 |
| 13 | 2002004266084 |
| 14 | 20000286620224 |
| 15 | 200080402620484 |
| 16 | 2000028662022400 |
| 17 | 20000086482842244 |
| 18 | 200002866202240000 |
| 19 | 2000008648284224400 |
| 20 | 20000246442286866064 |