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 | 8 |
| 3 | 23 |
| 4 | 73 |
| 5 | 251 |
| 6 | 919 |
| 7 | 3549 |
| 8 | 14371 |
| 9 | 60720 |
| 10 | 266481 |
| 11 | 1209807 |
| 12 | 5662008 |
| 13 | 27238884 |
| 14 | 134391046 |
| 15 | 678739990 |
| 16 | 3503708942 |
| 17 | 18462855900 |
| 18 | 99211177417 |
| 19 | 543161148837 |
| 20 | 3027439667989 |
| 21 | 17167987227428 |
| 22 | 98995692542858 |
| 23 | 580166879766649 |