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 | 2 |
| 2 | 7 |
| 3 | 18 |
| 4 | 47 |
| 5 | 118 |
| 6 | 290 |
| 7 | 702 |
| 8 | 1677 |
| 9 | 3966 |
| 10 | 9300 |
| 11 | 21654 |
| 12 | 50116 |
| 13 | 115388 |
| 14 | 264475 |
| 15 | 603792 |
| 16 | 1373621 |
| 17 | 3115222 |
| 18 | 7045205 |
| 19 | 15892794 |
| 20 | 35769390 |
| 21 | 80337144 |
| 22 | 180091131 |
| 23 | 403002108 |
| 24 | 900370600 |
| 25 | 2008572044 |
| 26 | 4474586920 |
| 27 | 9955434456 |
| 28 | 22123162421 |
| 29 | 49107537598 |
| 30 | 108891513251 |