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 | 1 |
| 2 | 4 |
| 3 | 16 |
| 4 | 106 |
| 5 | 861 |
| 6 | 7216 |
| 7 | 61938 |
| 8 | 541854 |
| 9 | 4814936 |
| 10 | 43336106 |
| 11 | 394050419 |
| 12 | 3612791400 |
| 13 | 33353349498 |
| 14 | 309745405634 |
| 15 | 2891246183239 |
| 16 | 27107799609004 |
| 17 | 255151905596682 |
| 18 | 2409933230413924 |
| 19 | 22832347500212719 |
| 20 | 216919281298152512 |
| 21 | 2066001163137387739 |
| 22 | 19721816247905813257 |