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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 1 |
| 6 | 6 |
| 7 | 15 |
| 8 | 9 |
| 9 | 1 |
| 10 | 10 |
| 11 | 45 |
| 12 | 120 |
| 13 | 162 |
| 14 | 109 |
| 15 | 27 |
| 16 | 1 |
| 17 | 15 |
| 18 | 105 |
| 19 | 455 |
| 20 | 1365 |
| 21 | 2755 |
| 22 | 3738 |
| 23 | 3353 |
| 24 | 1889 |
| 25 | 600 |
| 26 | 81 |
| 27 | 1 |
| 28 | 21 |
| 29 | 210 |
| 30 | 1330 |
| 31 | 5985 |
| 32 | 20349 |
| 33 | 52764 |
| 34 | 104726 |
| 35 | 159351 |
| 36 | 185155 |
| 37 | 162455 |
| 38 | 105436 |
| 39 | 48881 |
| 40 | 15255 |
| 41 | 2862 |
| 42 | 243 |
| 43 | 1 |
| 44 | 28 |
| 45 | 378 |
| 46 | 3276 |
| 47 | 20475 |
| 48 | 98280 |
| 49 | 376740 |
| 50 | 1173564 |
| 51 | 2995480 |
| 52 | 6295857 |
| 53 | 10925190 |
| 54 | 15658609 |
| 55 | 18498220 |
| 56 | 17926289 |
| 57 | 14138445 |
| 58 | 8968823 |
| 59 | 4498534 |
| 60 | 1740117 |
| 61 | 499834 |
| 62 | 100225 |
| 63 | 12501 |
| 64 | 729 |
[1,1,1,3,1,6,15,9,1,10,45,120,162,109,27,1,15,105, 455,1365,2755,3738,3353,1889,600,81,1,21,210,1330, 5985,20349,52764,104726,159351,185155,162455, 105436,48881,15255,2862,243,1,28,378,3276,20475, 98280,376740,1173564,2995480,6295857,10925190, 15658609,18498220,17926289,14138445,8968823, 4498534,1740117,499834,100225,12501,729] |