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 | 5 |
| 2 | 25 |
| 3 | 125 |
| 4 | 621 |
| 5 | 3065 |
| 6 | 15036 |
| 7 | 73348 |
| 8 | 355921 |
| 9 | 1718569 |
| 10 | 8259567 |
| 11 | 39522507 |
| 12 | 188338770 |
| 13 | 894017122 |
| 14 | 4228223130 |
| 15 | 19928007170 |
| 16 | 93614937601 |
| 17 | 438406639797 |
| 18 | 2047055696994 |
| 19 | 9531639358730 |
| 20 | 44264054228691 |
| 21 | 205038988521635 |
| 22 | 947492030288164 |