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 | 9 |
| 2 | 81 |
| 3 | 193 |
| 4 | 663 |
| 5 | 1664 |
| 6 | 4018 |
| 7 | 11509 |
| 8 | 30943 |
| 9 | 79178 |
| 10 | 213444 |
| 11 | 574517 |
| 12 | 1510235 |
| 13 | 4016905 |
| 14 | 10742833 |
| 15 | 28499913 |
| 16 | 75702647 |
| 17 | 201719465 |
| 18 | 536397481 |
| 19 | 1425655190 |
| 20 | 3793651190 |
| 21 | 10091485607 |
| 22 | 26833849671 |
| 23 | 71376964346 |
| 24 | 189863830540 |
| 25 | 504956635718 |