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 | 0 |
| 2 | 2 |
| 3 | 3 |
| 4 | 11 |
| 5 | 29 |
| 6 | 93 |
| 7 | 268 |
| 8 | 842 |
| 9 | 2547 |
| 10 | 7946 |
| 11 | 24539 |
| 12 | 76721 |
| 13 | 239462 |
| 14 | 751569 |
| 15 | 2360679 |
| 16 | 7437243 |
| 17 | 23461543 |
| 18 | 74155431 |
| 19 | 234687456 |
| 20 | 743792675 |
| 21 | 2359972537 |
| 22 | 7496293462 |
| 23 | 23834595755 |
| 24 | 75852059135 |
| 25 | 241594260984 |
| 26 | 770090455545 |
| 27 | 2456436981617 |