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) |
|---|---|
| 3 | 1 |
| 4 | 3 |
| 5 | 6 |
| 6 | 14 |
| 7 | 29 |
| 8 | 60 |
| 9 | 123 |
| 10 | 249 |
| 11 | 503 |
| 12 | 1012 |
| 13 | 2032 |
| 14 | 4075 |
| 15 | 8164 |
| 16 | 16347 |
| 17 | 32719 |
| 18 | 65471 |
| 19 | 130986 |
| 20 | 262030 |
| 21 | 524137 |
| 22 | 1048376 |
| 23 | 2096887 |
| 24 | 4193953 |
| 25 | 8388143 |
| 26 | 16776600 |
| 27 | 33553616 |
| 28 | 67107783 |
| 29 | 134216296 |
| 30 | 268433559 |
| 31 | 536868399 |
| 32 | 1073738495 |
| 33 | 2147479238 |
| 34 | 4294961454 |
| 35 | 8589926853 |
| 36 | 17179858932 |
| 37 | 34359724787 |
| 38 | 68719458745 |
| 39 | 137438929639 |
| 40 | 274877875372 |