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 | 0 |
| 2 | 1 |
| 3 | 25 |
| 4 | 26 |
| 5 | 51 |
| 6 | 119 |
| 7 | 218 |
| 8 | 771 |
| 9 | 1754 |
| 10 | 1799 |
| 11 | 1921 |
| 12 | 7967 |
| 13 | 16147 |
| 14 | 32639 |
| 15 | 128129 |
| 16 | 196611 |
| 17 | 458759 |
| 18 | 1044143 |
| 19 | 2031647 |
| 20 | 7190234 |
| 21 | 8323199 |
| 22 | 33464867 |
| 23 | 536581571 |
| 24 | 536813567 |
| 25 | 1073691551 |
| 26 | 2145328183 |
| 27 | 7202169026 |
| 28 | 8746826298 |
| 29 | 17179612627 |
| 30 | 68719005499 |
| 31 | 797299610790 |