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 | 261 |
| 4 | 841 |
| 5 | 4089 |
| 6 | 19881 |
| 7 | 80511 |
| 8 | 326041 |
| 9 | 1428071 |
| 10 | 6255001 |
| 11 | 26473085 |
| 12 | 112042225 |
| 13 | 481310535 |
| 14 | 2067611841 |
| 15 | 8824602441 |
| 16 | 37663553041 |
| 17 | 161202941369 |
| 18 | 689961148321 |
| 19 | 2949462033565 |
| 20 | 12608429197225 |
| 21 | 53927628353015 |
| 22 | 230654354661481 |