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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 35 |
| 5 | 135 |
| 6 | 541 |
| 7 | 2217 |
| 8 | 9377 |
| 9 | 40349 |
| 10 | 175942 |
| 11 | 778143 |
| 12 | 3477104 |
| 13 | 15671149 |
| 14 | 71188693 |
| 15 | 325532865 |
| 16 | 1497282449 |
| 17 | 6922353003 |
| 18 | 32148253707 |
| 19 | 149919105537 |
| 20 | 701702507444 |
| 21 | 3295012665703 |
| 22 | 15519855244683 |
| 23 | 73301505108780 |
| 24 | 347061046971505 |
| 25 | 1647058682479621 |
| 26 | 7833160088904523 |
| 27 | 37325460274234458 |
[1,1,3,10,35,135,541,2217,9377,40349,175942, 778143,3477104,15671149,71188693,325532865, 1497282449,6922353003,32148253707,149919105537, 701702507444,3295012665703,15519855244683, 73301505108780,347061046971505,1647058682479621, 7833160088904523,37325460274234458] |