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 | 2 |
| 3 | 4 |
| 4 | 10 |
| 5 | 26 |
| 6 | 78 |
| 7 | 236 |
| 8 | 770 |
| 9 | 2520 |
| 10 | 8606 |
| 11 | 29364 |
| 12 | 103302 |
| 13 | 362226 |
| 14 | 1298882 |
| 15 | 4645670 |
| 16 | 16897224 |
| 17 | 61296686 |
| 18 | 225457006 |
| 19 | 826950080 |
| 20 | 3067763394 |
| 21 | 11353597198 |
| 22 | 42414220022 |
| 23 | 158095481910 |
| 24 | 594108418428 |
| 25 | 2227714454332 |
| 26 | 8412269224862 |
| 27 | 31704876569698 |
| 28 | 120223392641084 |
| 29 | 455053649594196 |
| 30 | 1731861709709542 |
| 31 | 6579658381972974 |