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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 2 |
| 7 | 3 |
| 8 | 6 |
| 9 | 10 |
| 10 | 19 |
| 11 | 35 |
| 12 | 67 |
| 13 | 127 |
| 14 | 248 |
| 15 | 482 |
| 16 | 952 |
| 17 | 1885 |
| 18 | 3765 |
| 19 | 7546 |
| 20 | 15221 |
| 21 | 30802 |
| 22 | 62620 |
| 23 | 127702 |
| 24 | 261335 |
| 25 | 536278 |
| 26 | 1103600 |
| 27 | 2276499 |
| 28 | 4706985 |
| 29 | 9752585 |
| 30 | 20247033 |
| 31 | 42110393 |
| 32 | 87733197 |
| 33 | 183074638 |
| 34 | 382599946 |
| 35 | 800701320 |
| 36 | 1677922740 |
| 37 | 3520581954 |
[0,0,1,0,1,1,2,3,6,10,19,35,67,127,248,482,952, 1885,3765,7546,15221,30802,62620,127702,261335, 536278,1103600,2276499,4706985,9752585,20247033, 42110393,87733197,183074638,382599946,800701320, 1677922740,3520581954] |