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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 18 |
| 5 | 51 |
| 6 | 72 |
| 7 | 176 |
| 8 | 264 |
| 9 | 447 |
| 10 | 586 |
| 11 | 1128 |
| 12 | 1362 |
| 13 | 2374 |
| 14 | 2943 |
| 15 | 3868 |
| 16 | 4841 |
| 17 | 7578 |
| 18 | 8633 |
| 19 | 12828 |
| 20 | 14847 |
| 21 | 18432 |
| 22 | 21480 |
| 23 | 30081 |
| 24 | 33223 |
| 25 | 43022 |
| 26 | 49051 |
| 27 | 59449 |
| 28 | 66796 |
| 29 | 87627 |
| 30 | 93688 |
| 31 | 120554 |
| 32 | 134772 |
| 33 | 156325 |
| 34 | 173243 |
| 35 | 205164 |
| 36 | 219513 |
| 37 | 272331 |
| 38 | 298743 |
[1,3,9,18,51,72,176,264,447,586,1128,1362,2374, 2943,3868,4841,7578,8633,12828,14847,18432,21480, 30081,33223,43022,49051,59449,66796,87627,93688, 120554,134772,156325,173243,205164,219513,272331, 298743] |