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) |
|---|---|
| 2 | 1 |
| 3 | 7 |
| 4 | 28 |
| 5 | 86 |
| 6 | 227 |
| 7 | 545 |
| 8 | 1230 |
| 9 | 2664 |
| 10 | 5613 |
| 11 | 11611 |
| 12 | 23728 |
| 13 | 48106 |
| 14 | 97031 |
| 15 | 195077 |
| 16 | 391394 |
| 17 | 784284 |
| 18 | 1570353 |
| 19 | 3142815 |
| 20 | 6288100 |
| 21 | 12579070 |
| 22 | 25161451 |
| 23 | 50326697 |
| 24 | 100657718 |
| 25 | 201320336 |
| 26 | 402646197 |
| 27 | 805298595 |