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 | 1 |
| 2 | 5 |
| 3 | 31 |
| 4 | 169 |
| 5 | 841 |
| 6 | 3961 |
| 7 | 18019 |
| 8 | 80081 |
| 9 | 350065 |
| 10 | 1511641 |
| 11 | 6466461 |
| 12 | 27457585 |
| 13 | 115892401 |
| 14 | 486748081 |
| 15 | 2035917451 |
| 16 | 8485840801 |
| 17 | 35263382881 |
| 18 | 146157442201 |
| 19 | 604404010981 |
| 20 | 2494365759601 |
| 21 | 10275832148401 |
| 22 | 42264944401681 |
| 23 | 173588164506901 |
| 24 | 712027089322849 |