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| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 1 |
| 7 | 2 |
| 8 | 6 |
| 9 | 18 |
| 10 | 40 |
| 11 | 24 |
| 12 | 6 |
| 13 | 1 |
| 14 | 2 |
| 15 | 6 |
| 16 | 20 |
| 17 | 72 |
| 18 | 248 |
| 19 | 698 |
| 20 | 1100 |
| 21 | 1096 |
| 22 | 662 |
| 23 | 206 |
| 24 | 1 |
| 25 | 2 |
| 26 | 6 |
| 27 | 20 |
| 28 | 74 |
| 29 | 298 |
| 30 | 1228 |
| 31 | 4762 |
| 32 | 15984 |
| 33 | 40026 |
| 34 | 75524 |
| 35 | 109150 |
| 36 | 121130 |
| 37 | 99032 |
| 38 | 51964 |
| 39 | 11996 |
| 40 | 1072 |
| 41 | 1 |
| 42 | 2 |
| 43 | 6 |
| 44 | 20 |
| 45 | 74 |
| 46 | 300 |
| 47 | 1300 |
| 48 | 5844 |
| 49 | 26148 |
| 50 | 110942 |
| 51 | 427388 |
| 52 | 1393796 |
| 53 | 3790524 |
| 54 | 8648638 |
| 55 | 16727776 |
| 56 | 27529284 |
| 57 | 38120312 |
| 58 | 43012614 |
| 59 | 37385280 |
| 60 | 23166526 |
| 61 | 9496426 |
| 62 | 2286972 |
| 63 | 242764 |
[1,1,2,4,1,2,6,18,40,24,6,1,2,6,20,72,248,698, 1100,1096,662,206,1,2,6,20,74,298,1228,4762,15984, 40026,75524,109150,121130,99032,51964,11996,1072, 1,2,6,20,74,300,1300,5844,26148,110942,427388, 1393796,3790524,8648638,16727776,27529284, 38120312,43012614,37385280,23166526,9496426, 2286972,242764] |