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 | 7 |
| 3 | 20 |
| 4 | 69 |
| 5 | 178 |
| 6 | 571 |
| 7 | 1451 |
| 8 | 4108 |
| 9 | 10480 |
| 10 | 27578 |
| 11 | 68401 |
| 12 | 172818 |
| 13 | 417979 |
| 14 | 1017575 |
| 15 | 2410964 |
| 16 | 5702481 |
| 17 | 13228877 |
| 18 | 30573978 |
| 19 | 69594694 |
| 20 | 157597162 |
| 21 | 352694078 |
| 22 | 784615466 |
| 23 | 1728604925 |
| 24 | 3785636280 |
| 25 | 8221695626 |
| 26 | 17751593170 |
| 27 | 38051212654 |
| 28 | 81103710142 |
| 29 | 171757084527 |