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 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 25 |
| 5 | 121 |
| 6 | 361 |
| 7 | 841 |
| 8 | 82321 |
| 9 | 728785 |
| 10 | 3633841 |
| 11 | 13313521 |
| 12 | 2195435881 |
| 13 | 28125394441 |
| 14 | 196393341145 |
| 15 | 981274727161 |
| 16 | 227100486456481 |
| 17 | 3807339471993121 |
| 18 | 34186011461595361 |
| 19 | 216366574074187105 |
| 20 | 64438384450412161081 |
| 21 | 1335035336388170601241 |