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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 4 |
| 8 | 8 |
| 9 | 15 |
| 10 | 24 |
| 11 | 48 |
| 12 | 85 |
| 13 | 155 |
| 14 | 297 |
| 15 | 541 |
| 16 | 1024 |
| 17 | 1935 |
| 18 | 3626 |
| 19 | 6912 |
| 20 | 13107 |
| 21 | 24940 |
| 22 | 47709 |
| 23 | 91136 |
| 24 | 174760 |
| 25 | 335626 |
| 26 | 645120 |
| 27 | 1242904 |
| 28 | 2396745 |
| 29 | 4627915 |
| 30 | 8948385 |
| 31 | 17317888 |
| 32 | 33554432 |
| 33 | 65076240 |
| 34 | 126320640 |
| 35 | 245428574 |
| 36 | 477218560 |
| 37 | 928638035 |
| 38 | 1808414181 |
| 39 | 3524068955 |
| 40 | 6871947672 |
| 41 | 13408691175 |
| 42 | 26178823218 |
[1,0,1,1,1,3,4,8,15,24,48,85,155,297,541,1024, 1935,3626,6912,13107,24940,47709,91136,174760, 335626,645120,1242904,2396745,4627915,8948385, 17317888,33554432,65076240,126320640,245428574, 477218560,928638035,1808414181,3524068955, 6871947672,13408691175,26178823218] |