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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 2 |
| 8 | 6 |
| 9 | 5 |
| 10 | 16 |
| 11 | 13 |
| 12 | 45 |
| 13 | 39 |
| 14 | 138 |
| 15 | 122 |
| 16 | 439 |
| 17 | 392 |
| 18 | 1417 |
| 19 | 1286 |
| 20 | 4698 |
| 21 | 4341 |
| 22 | 16021 |
| 23 | 14860 |
| 24 | 55146 |
| 25 | 51085 |
| 26 | 190274 |
| 27 | 178402 |
| 28 | 671224 |
| 29 | 634511 |
| 30 | 2404289 |
| 31 | 2260918 |
| 32 | 8535117 |
| 33 | 8067237 |
| 34 | 30635869 |
| 35 | 29031202 |
| 36 | 110496946 |
| 37 | 105250449 |
| 38 | 401422210 |
| 39 | 383579285 |
| 40 | 1467402238 |
[1,0,1,1,1,1,3,2,6,5,16,13,45,39,138,122,439,392, 1417,1286,4698,4341,16021,14860,55146,51085, 190274,178402,671224,634511,2404289,2260918, 8535117,8067237,30635869,29031202,110496946, 105250449,401422210,383579285,1467402238] |