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 | 2 |
| 3 | 8 |
| 4 | 52 |
| 5 | 248 |
| 6 | 1302 |
| 7 | 6448 |
| 8 | 32552 |
| 9 | 162448 |
| 10 | 813802 |
| 11 | 4067448 |
| 12 | 20345052 |
| 13 | 101717448 |
| 14 | 508626302 |
| 15 | 2543092448 |
| 16 | 12715657552 |
| 17 | 63578092448 |
| 18 | 317891438802 |
| 19 | 1589456217448 |
| 20 | 7947285970052 |
| 21 | 39736424967448 |
| 22 | 198682149251302 |
| 23 | 993410721842448 |
| 24 | 4967053731282552 |