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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 2 |
| 4 | 1 |
| 5 | 5 |
| 6 | 4 |
| 7 | 16 |
| 8 | 13 |
| 9 | 54 |
| 10 | 46 |
| 11 | 186 |
| 12 | 167 |
| 13 | 660 |
| 14 | 612 |
| 15 | 2384 |
| 16 | 2267 |
| 17 | 8726 |
| 18 | 8464 |
| 19 | 32278 |
| 20 | 31822 |
| 21 | 120419 |
| 22 | 120338 |
| 23 | 452420 |
| 24 | 457320 |
| 25 | 1709845 |
| 26 | 1745438 |
| 27 | 6494848 |
| 28 | 6686929 |
| 29 | 24779026 |
| 30 | 25703792 |
| 31 | 94899470 |
| 32 | 99096382 |
| 33 | 364680344 |
[1,0,2,1,5,4,16,13,54,46,186,167,660,612,2384, 2267,8726,8464,32278,31822,120419,120338,452420, 457320,1709845,1745438,6494848,6686929,24779026, 25703792,94899470,99096382,364680344] |