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 | 5 |
| 3 | 19 |
| 4 | 66 |
| 5 | 216 |
| 6 | 679 |
| 7 | 2075 |
| 8 | 6211 |
| 9 | 18299 |
| 10 | 53244 |
| 11 | 153366 |
| 12 | 438095 |
| 13 | 1242709 |
| 14 | 3504161 |
| 15 | 9830371 |
| 16 | 27454614 |
| 17 | 76375860 |
| 18 | 211732471 |
| 19 | 585157679 |
| 20 | 1612689439 |
| 21 | 4433421131 |
| 22 | 12160156560 |
| 23 | 33284285874 |
| 24 | 90931830431 |
| 25 | 247991356201 |
| 26 | 675243561149 |
| 27 | 1835863145395 |
| 28 | 4984516006506 |
| 29 | 13516071450384 |