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 | 21 |
| 2 | 438 |
| 3 | 9516 |
| 4 | 201960 |
| 5 | 4299802 |
| 6 | 91513161 |
| 7 | 1948262831 |
| 8 | 41475009100 |
| 9 | 882920599454 |
| 10 | 18795714385533 |
| 11 | 400125250527550 |
| 12 | 8517908622924528 |
| 13 | 181330147341356981 |
| 14 | 3860175542316616321 |
| 15 | 82175828913427711206 |
| 16 | 1749367816354069818496 |