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 | 20 |
| 2 | 420 |
| 3 | 7831 |
| 4 | 128232 |
| 5 | 1971414 |
| 6 | 29134076 |
| 7 | 418632185 |
| 8 | 5894815754 |
| 9 | 81718671716 |
| 10 | 1119014223138 |
| 11 | 15171181272721 |
| 12 | 203998929406004 |
| 13 | 2724149465085496 |
| 14 | 36163754541884778 |
| 15 | 477648079847735215 |
| 16 | 6280858615510607492 |