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 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 11 |
| 6 | 24 |
| 7 | 58 |
| 8 | 149 |
| 9 | 385 |
| 10 | 1001 |
| 11 | 2652 |
| 12 | 7140 |
| 13 | 19384 |
| 14 | 52944 |
| 15 | 145590 |
| 16 | 402949 |
| 17 | 1121117 |
| 18 | 3133255 |
| 19 | 8793372 |
| 20 | 24774557 |
| 21 | 70045871 |
| 22 | 198672464 |
| 23 | 565144064 |
| 24 | 1611946284 |
| 25 | 4609140916 |
| 26 | 13209415116 |
| 27 | 37937455636 |
| 28 | 109171460104 |
| 29 | 314736939884 |
| 30 | 908930799572 |
| 31 | 2629120466966 |