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 | 4 |
| 2 | 9 |
| 3 | 14 |
| 4 | 155 |
| 5 | 2993 |
| 6 | 9707 |
| 7 | 184183 |
| 8 | 331981 |
| 9 | 1942071 |
| 10 | 1263047761 |
| 11 | 140390505643 |
| 12 | 455845099957 |
| 13 | 296452328830865 |
| 14 | 32951342156444219 |
| 15 | 2381929669709247097441 |
| 16 | 9063289616192276216577361 |
| 17 | 34485996673867704851362967681 |
| 18 | 426068342298911680872493712146539 |
| 19 | 117190394374593808526426397401539675762247 |