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 | 1 |
| 2 | 4 |
| 3 | 48 |
| 4 | 320 |
| 5 | 1610 |
| 6 | 6012 |
| 7 | 17948 |
| 8 | 45488 |
| 9 | 101970 |
| 10 | 207920 |
| 11 | 393272 |
| 12 | 699888 |
| 13 | 1184378 |
| 14 | 1921220 |
| 15 | 3006180 |
| 16 | 4560032 |
| 17 | 6732578 |
| 18 | 9706968 |
| 19 | 13704320 |
| 20 | 18988640 |
| 21 | 25872042 |
| 22 | 34720268 |
| 23 | 45958508 |
| 24 | 60077520 |
| 25 | 77640050 |
| 26 | 99287552 |
| 27 | 125747208 |
| 28 | 157839248 |
| 29 | 196484570 |
| 30 | 242712660 |