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 | 19 |
| 3 | 132 |
| 4 | 1253 |
| 5 | 14808 |
| 6 | 206503 |
| 7 | 3298552 |
| 8 | 59220265 |
| 9 | 1179047100 |
| 10 | 25767347387 |
| 11 | 613141219356 |
| 12 | 15780105110605 |
| 13 | 436801028784112 |
| 14 | 12941788708753999 |
| 15 | 408718346076189360 |
| 16 | 13707898517284016849 |
| 17 | 486640514520848512692 |