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 | 8 |
| 2 | 64 |
| 3 | 520 |
| 4 | 4304 |
| 5 | 36232 |
| 6 | 309504 |
| 7 | 2677128 |
| 8 | 23405520 |
| 9 | 206522888 |
| 10 | 1836913216 |
| 11 | 16452907016 |
| 12 | 148274884688 |
| 13 | 1343569891720 |
| 14 | 12233903203328 |
| 15 | 111883174439304 |
| 16 | 1027244073375312 |
| 17 | 9465236716896264 |
| 18 | 87498251217286720 |
| 19 | 811252609543727624 |
| 20 | 7542152541765899728 |
| 21 | 70294794046928531848 |