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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 3 |
| 4 | 6 |
| 5 | 12 |
| 6 | 6 |
| 7 | 10 |
| 8 | 33 |
| 9 | 33 |
| 10 | 10 |
| 11 | 15 |
| 12 | 72 |
| 13 | 135 |
| 14 | 72 |
| 15 | 15 |
| 16 | 21 |
| 17 | 135 |
| 18 | 438 |
| 19 | 438 |
| 20 | 135 |
| 21 | 21 |
| 22 | 28 |
| 23 | 228 |
| 24 | 1140 |
| 25 | 2224 |
| 26 | 1140 |
| 27 | 228 |
| 28 | 28 |
| 29 | 36 |
| 30 | 357 |
| 31 | 2511 |
| 32 | 8850 |
| 33 | 8850 |
| 34 | 2511 |
| 35 | 357 |
| 36 | 36 |
| 37 | 45 |
| 38 | 528 |
| 39 | 4893 |
| 40 | 27480 |
| 41 | 55725 |
| 42 | 27480 |
| 43 | 4893 |
| 44 | 528 |
| 45 | 45 |
| 46 | 55 |
| 47 | 747 |
| 48 | 8700 |
| 49 | 70462 |
| 50 | 265665 |
| 51 | 265665 |
| 52 | 70462 |
| 53 | 8700 |
| 54 | 747 |
| 55 | 55 |
[1,3,3,6,12,6,10,33,33,10,15,72,135,72,15,21,135, 438,438,135,21,28,228,1140,2224,1140,228,28,36, 357,2511,8850,8850,2511,357,36,45,528,4893,27480, 55725,27480,4893,528,45,55,747,8700,70462,265665, 265665,70462,8700,747,55] |