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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 0 |
| 5 | 9 |
| 6 | 0 |
| 7 | 1 |
| 8 | 44 |
| 9 | 64 |
| 10 | 0 |
| 11 | 0 |
| 12 | 446 |
| 13 | 664 |
| 14 | 441 |
| 15 | 0 |
| 16 | 1 |
| 17 | 3334 |
| 18 | 31663 |
| 19 | 12495 |
| 20 | 3025 |
| 21 | 0 |
| 22 | 0 |
| 23 | 27540 |
| 24 | 730874 |
| 25 | 2691211 |
| 26 | 221614 |
| 27 | 20736 |
| 28 | 0 |
| 29 | 1 |
| 30 | 219070 |
| 31 | 22664752 |
| 32 | 223123842 |
| 33 | 219689604 |
| 34 | 4010052 |
| 35 | 142129 |
| 36 | 0 |
| 37 | 0 |
| 38 | 1766136 |
| 39 | 617892584 |
| 40 | 26917553016 |
| 41 | 61691224718 |
[0,1,0,0,9,0,1,44,64,0,0,446,664,441,0,1,3334, 31663,12495,3025,0,0,27540,730874,2691211,221614, 20736,0,1,219070,22664752,223123842,219689604, 4010052,142129,0,0,1766136,617892584,26917553016, 61691224718] |