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 | 4 |
| 2 | 37 |
| 3 | 520 |
| 4 | 8803 |
| 5 | 165292 |
| 6 | 3320023 |
| 7 | 69943804 |
| 8 | 1526981575 |
| 9 | 34271322316 |
| 10 | 786371041603 |
| 11 | 18372739163632 |
| 12 | 435772652437381 |
| 13 | 10468369504009060 |
| 14 | 254238148448959729 |
| 15 | 6233226769739934964 |
| 16 | 154092763036678601551 |
| 17 | 3837301178450916902428 |
| 18 | 96181503100227675085675 |