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 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 18 |
| 5 | 46 |
| 6 | 121 |
| 7 | 323 |
| 8 | 875 |
| 9 | 2395 |
| 10 | 6611 |
| 11 | 18371 |
| 12 | 51337 |
| 13 | 144145 |
| 14 | 406420 |
| 15 | 1150126 |
| 16 | 3265412 |
| 17 | 9298372 |
| 18 | 26547710 |
| 19 | 75978322 |
| 20 | 217921336 |
| 21 | 626287520 |
| 22 | 1803176384 |
| 23 | 5200298000 |
| 24 | 15020569818 |
| 25 | 43447201226 |
| 26 | 125837214564 |
| 27 | 364911724264 |
| 28 | 1059404265599 |
| 29 | 3078918594707 |