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 | 3 |
| 2 | 6 |
| 3 | 16 |
| 4 | 48 |
| 5 | 153 |
| 6 | 511 |
| 7 | 1761 |
| 8 | 6219 |
| 9 | 22383 |
| 10 | 81804 |
| 11 | 302766 |
| 12 | 1132475 |
| 13 | 4274166 |
| 14 | 16256685 |
| 15 | 62249167 |
| 16 | 239772510 |
| 17 | 928398831 |
| 18 | 3611539758 |
| 19 | 14107963848 |
| 20 | 55318781982 |
| 21 | 217652858539 |
| 22 | 859027927911 |
| 23 | 3400055112777 |
| 24 | 13492710661658 |
| 25 | 53673238384560 |
| 26 | 213984657134418 |