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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 2 |
| 4 | 1 |
| 5 | 0 |
| 6 | 0 |
| 7 | 12 |
| 8 | 20 |
| 9 | 15 |
| 10 | 6 |
| 11 | 1 |
| 12 | 0 |
| 13 | 0 |
| 14 | 0 |
| 15 | 104 |
| 16 | 426 |
| 17 | 768 |
| 18 | 920 |
| 19 | 792 |
| 20 | 495 |
| 21 | 220 |
| 22 | 66 |
| 23 | 12 |
| 24 | 1 |
| 25 | 0 |
| 26 | 0 |
| 27 | 0 |
| 28 | 0 |
| 29 | 1160 |
| 30 | 9184 |
| 31 | 32420 |
| 32 | 73000 |
| 33 | 123425 |
| 34 | 166860 |
| 35 | 184426 |
| 36 | 167900 |
| 37 | 125965 |
| 38 | 77520 |
| 39 | 38760 |
| 40 | 15504 |
| 41 | 4845 |
| 42 | 1140 |
| 43 | 190 |
| 44 | 20 |
| 45 | 1 |
[1,0,2,1,0,0,12,20,15,6,1,0,0,0,104,426,768,920, 792,495,220,66,12,1,0,0,0,0,1160,9184,32420,73000, 123425,166860,184426,167900,125965,77520,38760, 15504,4845,1140,190,20,1] |