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) |
|---|---|
| 1 | 2 |
| 2 | 4 |
| 3 | 13 |
| 4 | 40 |
| 5 | 125 |
| 6 | 393 |
| 7 | 1200 |
| 8 | 3759 |
| 9 | 11572 |
| 10 | 36004 |
| 11 | 111380 |
| 12 | 345489 |
| 13 | 1070564 |
| 14 | 3318409 |
| 15 | 10285305 |
| 16 | 31878944 |
| 17 | 98808901 |
| 18 | 306255436 |
| 19 | 949236490 |
| 20 | 2942139012 |
| 21 | 9119124333 |
| 22 | 28264569620 |
| 23 | 87605626309 |
| 24 | 271532263929 |
| 25 | 841610129904 |
| 26 | 2608557687707 |