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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 6 |
| 6 | 12 |
| 7 | 27 |
| 8 | 63 |
| 9 | 155 |
| 10 | 402 |
| 11 | 1087 |
| 12 | 3068 |
| 13 | 8996 |
| 14 | 27340 |
| 15 | 85905 |
| 16 | 278485 |
| 17 | 929713 |
| 18 | 3191201 |
| 19 | 11245603 |
| 20 | 40631628 |
| 21 | 150342633 |
| 22 | 569071745 |
| 23 | 2201355134 |
| 24 | 8694775795 |
| 25 | 35035655103 |
| 26 | 143916920872 |
| 27 | 602218550964 |
| 28 | 2565370007349 |
| 29 | 11118142868084 |
| 30 | 48994958103507 |
[1,1,1,2,3,6,12,27,63,155,402,1087,3068,8996, 27340,85905,278485,929713,3191201,11245603, 40631628,150342633,569071745,2201355134, 8694775795,35035655103,143916920872,602218550964, 2565370007349,11118142868084,48994958103507] |