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 | 1 |
| 2 | 4 |
| 3 | 17 |
| 4 | 76 |
| 5 | 336 |
| 6 | 1484 |
| 7 | 6559 |
| 8 | 28988 |
| 9 | 128111 |
| 10 | 566184 |
| 11 | 2502240 |
| 12 | 11058600 |
| 13 | 48873265 |
| 14 | 215994436 |
| 15 | 954583169 |
| 16 | 4218761572 |
| 17 | 18644733936 |
| 18 | 82400035556 |
| 19 | 364165339279 |
| 20 | 1609421566844 |
| 21 | 7112807014943 |
| 22 | 31434910948176 |
| 23 | 138925971735744 |
| 24 | 613980604384080 |
| 25 | 2713475226049825 |