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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 0 |
| 3 | 1 |
| 4 | 0 |
| 5 | 3 |
| 6 | 28 |
| 7 | 45 |
| 8 | 276 |
| 9 | 595 |
| 10 | 1128 |
| 11 | 1953 |
| 12 | 3160 |
| 13 | 4851 |
| 14 | 264540 |
| 15 | 190333 |
| 16 | 254268 |
| 17 | 18915 |
| 18 | 3366496 |
| 19 | 32385 |
| 20 | 125391168 |
| 21 | 199588483 |
| 22 | 64620 |
| 23 | 174673821 |
| 24 | 5039370820 |
| 25 | 1784859363 |
| 26 | 16908230328 |
| 27 | 165025 |
| 28 | 34420237176 |
| 29 | 58409997075 |
| 30 | 1367074573228 |
| 31 | 2294838551853 |
| 32 | 15289788305820 |
[3,0,1,0,3,28,45,276,595,1128,1953,3160,4851, 264540,190333,254268,18915,3366496,32385, 125391168,199588483,64620,174673821,5039370820, 1784859363,16908230328,165025,34420237176, 58409997075,1367074573228,2294838551853, 15289788305820] |