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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 0 |
| 5 | 1 |
| 6 | 2 |
| 7 | 1 |
| 8 | 4 |
| 9 | 3 |
| 10 | 6 |
| 11 | 10 |
| 12 | 8 |
| 13 | 19 |
| 14 | 22 |
| 15 | 26 |
| 16 | 48 |
| 17 | 53 |
| 18 | 78 |
| 19 | 112 |
| 20 | 136 |
| 21 | 205 |
| 22 | 264 |
| 23 | 354 |
| 24 | 504 |
| 25 | 639 |
| 26 | 890 |
| 27 | 1204 |
| 28 | 1568 |
| 29 | 2173 |
| 30 | 2868 |
| 31 | 3826 |
| 32 | 5192 |
| 33 | 6839 |
| 34 | 9214 |
| 35 | 12295 |
| 36 | 16296 |
| 37 | 21894 |
| 38 | 28996 |
| 39 | 38624 |
| 40 | 51552 |
| 41 | 68230 |
| 42 | 90930 |
| 43 | 120715 |
| 44 | 159988 |
| 45 | 212728 |
| 46 | 281696 |
| 47 | 373574 |
| 48 | 495312 |
| 49 | 655365 |
| 50 | 868510 |
| 51 | 1149161 |
| 52 | 1520020 |
| 53 | 2011591 |
| 54 | 2658416 |
| 55 | 3514446 |
[0,0,1,0,1,2,1,4,3,6,10,8,19,22,26,48,53,78,112, 136,205,264,354,504,639,890,1204,1568,2173,2868, 3826,5192,6839,9214,12295,16296,21894,28996,38624, 51552,68230,90930,120715,159988,212728,281696, 373574,495312,655365,868510,1149161,1520020, 2011591,2658416,3514446] |