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 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 9 |
| 5 | 21 |
| 6 | 52 |
| 7 | 129 |
| 8 | 332 |
| 9 | 859 |
| 10 | 2261 |
| 11 | 5983 |
| 12 | 15976 |
| 13 | 42836 |
| 14 | 115469 |
| 15 | 312246 |
| 16 | 847241 |
| 17 | 2304522 |
| 18 | 6283327 |
| 19 | 17164401 |
| 20 | 46972357 |
| 21 | 128741107 |
| 22 | 353345434 |
| 23 | 970999198 |
| 24 | 2671347292 |
| 25 | 7356752678 |
| 26 | 20279171785 |
| 27 | 55948407837 |
| 28 | 154479213626 |
| 29 | 426845422807 |
| 30 | 1180229767202 |