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 | 3 |
| 2 | 12 |
| 3 | 37 |
| 4 | 111 |
| 5 | 315 |
| 6 | 864 |
| 7 | 2307 |
| 8 | 6027 |
| 9 | 15471 |
| 10 | 39132 |
| 11 | 97755 |
| 12 | 241606 |
| 13 | 591636 |
| 14 | 1437078 |
| 15 | 3465748 |
| 16 | 8305161 |
| 17 | 19788957 |
| 18 | 46910232 |
| 19 | 110686101 |
| 20 | 260064912 |
| 21 | 608684490 |
| 22 | 1419591546 |
| 23 | 3300027546 |
| 24 | 7648265728 |
| 25 | 17676484410 |
| 26 | 40747630332 |
| 27 | 93704299336 |
| 28 | 214999206831 |
| 29 | 492262973433 |