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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 16 |
| 5 | 55 |
| 6 | 71 |
| 7 | 126 |
| 8 | 7379 |
| 9 | 7505 |
| 10 | 14884 |
| 11 | 52157 |
| 12 | 119198 |
| 13 | 409751 |
| 14 | 528949 |
| 15 | 938700 |
| 16 | 54973549 |
| 17 | 55912249 |
| 18 | 110885798 |
| 19 | 388569643 |
| 20 | 888025084 |
| 21 | 3052644895 |
| 22 | 3940669979 |
| 23 | 6993314874 |
| 24 | 409552932671 |
| 25 | 416546247545 |
| 26 | 826099180216 |
| 27 | 2894843788193 |
| 28 | 6615786756602 |
[1,1,2,7,16,55,71,126,7379,7505,14884,52157, 119198,409751,528949,938700,54973549,55912249, 110885798,388569643,888025084,3052644895, 3940669979,6993314874,409552932671,416546247545, 826099180216,2894843788193,6615786756602] |