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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 2 |
| 5 | 4 |
| 6 | 10 |
| 7 | 3 |
| 8 | 7 |
| 9 | 21 |
| 10 | 73 |
| 11 | 2 |
| 12 | 6 |
| 13 | 26 |
| 14 | 126 |
| 15 | 626 |
| 16 | 4 |
| 17 | 12 |
| 18 | 50 |
| 19 | 252 |
| 20 | 1394 |
| 21 | 8052 |
| 22 | 2 |
| 23 | 8 |
| 24 | 50 |
| 25 | 344 |
| 26 | 2402 |
| 27 | 16808 |
| 28 | 117650 |
| 29 | 4 |
| 30 | 15 |
| 31 | 85 |
| 32 | 585 |
| 33 | 4369 |
| 34 | 33825 |
| 35 | 266305 |
| 36 | 2113665 |
| 37 | 3 |
| 38 | 13 |
| 39 | 91 |
| 40 | 757 |
| 41 | 6643 |
| 42 | 59293 |
| 43 | 532171 |
| 44 | 4785157 |
| 45 | 43053283 |
| 46 | 4 |
| 47 | 18 |
| 48 | 130 |
| 49 | 1134 |
| 50 | 10642 |
| 51 | 103158 |
| 52 | 1015690 |
| 53 | 10078254 |
| 54 | 100390882 |
| 55 | 1001953638 |
[1,2,3,2,4,10,3,7,21,73,2,6,26,126,626,4,12,50, 252,1394,8052,2,8,50,344,2402,16808,117650,4,15, 85,585,4369,33825,266305,2113665,3,13,91,757,6643, 59293,532171,4785157,43053283,4,18,130,1134,10642, 103158,1015690,10078254,100390882,1001953638] |