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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 30 |
| 5 | 87 |
| 6 | 249 |
| 7 | 705 |
| 8 | 1974 |
| 9 | 5471 |
| 10 | 15032 |
| 11 | 40997 |
| 12 | 111079 |
| 13 | 299151 |
| 14 | 801139 |
| 15 | 2134251 |
| 16 | 5657895 |
| 17 | 14930596 |
| 18 | 39232009 |
| 19 | 102673794 |
| 20 | 267692321 |
| 21 | 695440442 |
| 22 | 1800582809 |
| 23 | 4646964755 |
| 24 | 11956293758 |
| 25 | 30673060344 |
| 26 | 78470890246 |
| 27 | 200218512582 |
| 28 | 509557661691 |
| 29 | 1293664233400 |
| 30 | 3276659862518 |
[1,1,3,10,30,87,249,705,1974,5471,15032,40997, 111079,299151,801139,2134251,5657895,14930596, 39232009,102673794,267692321,695440442,1800582809, 4646964755,11956293758,30673060344,78470890246, 200218512582,509557661691,1293664233400, 3276659862518] |