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 | 2 |
| 2 | 4 |
| 3 | 10 |
| 4 | 24 |
| 5 | 60 |
| 6 | 148 |
| 7 | 370 |
| 8 | 920 |
| 9 | 2296 |
| 10 | 5720 |
| 11 | 14268 |
| 12 | 35568 |
| 13 | 88700 |
| 14 | 221156 |
| 15 | 551482 |
| 16 | 1375096 |
| 17 | 3428888 |
| 18 | 8549944 |
| 19 | 21319624 |
| 20 | 53160896 |
| 21 | 132558360 |
| 22 | 330537528 |
| 23 | 824204780 |
| 24 | 2055176304 |
| 25 | 5124638944 |
| 26 | 12778424976 |
| 27 | 31863351980 |
| 28 | 79452130896 |
| 29 | 198116051644 |
| 30 | 494007751668 |