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 | 0 |
| 1 | 3 |
| 2 | 14 |
| 3 | 55 |
| 4 | 209 |
| 5 | 791 |
| 6 | 3002 |
| 7 | 11439 |
| 8 | 43757 |
| 9 | 167959 |
| 10 | 646645 |
| 11 | 2496143 |
| 12 | 9657699 |
| 13 | 37442159 |
| 14 | 145422674 |
| 15 | 565722719 |
| 16 | 2203961429 |
| 17 | 8597496599 |
| 18 | 33578000609 |
| 19 | 131282408399 |
| 20 | 513791607419 |
| 21 | 2012616400079 |
| 22 | 7890371113949 |
| 23 | 30957699535775 |
| 24 | 121548660036299 |
| 25 | 477551179875951 |