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 | 3 |
| 3 | 7 |
| 4 | 11 |
| 5 | 347 |
| 6 | 3289 |
| 7 | 1011 |
| 8 | 38371 |
| 9 | 136553 |
| 10 | 4320019 |
| 11 | 12528587 |
| 12 | 40771123 |
| 13 | 29346499543 |
| 14 | 129990006917 |
| 15 | 1927874590951 |
| 16 | 903657004321 |
| 17 | 437445829053473 |
| 18 | 12456509813711881 |
| 19 | 187206004658210129 |
| 20 | 1974369484466728177 |
| 21 | 1967745662306280217 |
| 22 | 21401375717067880189 |