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 | 6 |
| 1 | 25 |
| 2 | 101 |
| 3 | 405 |
| 4 | 1621 |
| 5 | 6485 |
| 6 | 25941 |
| 7 | 103765 |
| 8 | 415061 |
| 9 | 1660245 |
| 10 | 6640981 |
| 11 | 26563925 |
| 12 | 106255701 |
| 13 | 425022805 |
| 14 | 1700091221 |
| 15 | 6800364885 |
| 16 | 27201459541 |
| 17 | 108805838165 |
| 18 | 435223352661 |
| 19 | 1740893410645 |
| 20 | 6963573642581 |
| 21 | 27854294570325 |
| 22 | 111417178281301 |
| 23 | 445668713125205 |