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 | 5 |
| 1 | 13 |
| 2 | 33 |
| 3 | 83 |
| 4 | 208 |
| 5 | 521 |
| 6 | 1305 |
| 7 | 3268 |
| 8 | 8183 |
| 9 | 20490 |
| 10 | 51306 |
| 11 | 128467 |
| 12 | 321673 |
| 13 | 805448 |
| 14 | 2016788 |
| 15 | 5049902 |
| 16 | 12644616 |
| 17 | 31661270 |
| 18 | 79277695 |
| 19 | 198506027 |
| 20 | 497045767 |
| 21 | 1244569236 |
| 22 | 3116317824 |
| 23 | 7803050645 |
| 24 | 19538315026 |
| 25 | 48922629292 |
| 26 | 122498979756 |
| 27 | 306729222415 |
| 28 | 768029383352 |
| 29 | 1923094020999 |
| 30 | 4815298338536 |