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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 3 |
| 7 | 3 |
| 8 | 2 |
| 9 | 6 |
| 10 | 15 |
| 11 | 21 |
| 12 | 24 |
| 13 | 42 |
| 14 | 86 |
| 15 | 138 |
| 16 | 192 |
| 17 | 305 |
| 18 | 546 |
| 19 | 906 |
| 20 | 1381 |
| 21 | 2175 |
| 22 | 3651 |
| 23 | 6042 |
| 24 | 9582 |
| 25 | 15225 |
| 26 | 24901 |
| 27 | 40836 |
| 28 | 65748 |
| 29 | 105364 |
| 30 | 170796 |
| 31 | 278184 |
| 32 | 450017 |
| 33 | 724968 |
| 34 | 1172412 |
| 35 | 1902321 |
| 36 | 3080367 |
| 37 | 4975551 |
| 38 | 8044478 |
| 39 | 13029534 |
| 40 | 21096027 |
| 41 | 34114553 |
[0,1,0,0,1,3,3,2,6,15,21,24,42,86,138,192,305,546, 906,1381,2175,3651,6042,9582,15225,24901,40836, 65748,105364,170796,278184,450017,724968,1172412, 1902321,3080367,4975551,8044478,13029534,21096027, 34114553] |