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 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 4 |
| 8 | 10 |
| 9 | 18 |
| 10 | 39 |
| 11 | 75 |
| 12 | 153 |
| 13 | 302 |
| 14 | 608 |
| 15 | 1212 |
| 16 | 2429 |
| 17 | 4853 |
| 18 | 9711 |
| 19 | 19416 |
| 20 | 38838 |
| 21 | 77670 |
| 22 | 155347 |
| 23 | 310687 |
| 24 | 621381 |
| 25 | 1242754 |
| 26 | 2485516 |
| 27 | 4971024 |
| 28 | 9942057 |
| 29 | 19884105 |
| 30 | 39768219 |
| 31 | 79536428 |
| 32 | 159072866 |
| 33 | 318145722 |
| 34 | 636291455 |
| 35 | 1272582899 |
| 36 | 2545165809 |
| 37 | 5090331606 |
| 38 | 10180663224 |
| 39 | 20361326436 |
| 40 | 40722652885 |
| 41 | 81445305757 |