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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 14 |
| 5 | 33 |
| 6 | 79 |
| 7 | 188 |
| 8 | 448 |
| 9 | 1068 |
| 10 | 2545 |
| 11 | 6065 |
| 12 | 14454 |
| 13 | 34446 |
| 14 | 82090 |
| 15 | 195633 |
| 16 | 466223 |
| 17 | 1111080 |
| 18 | 2647872 |
| 19 | 6310280 |
| 20 | 15038353 |
| 21 | 35838673 |
| 22 | 85408986 |
| 23 | 203542550 |
| 24 | 485072726 |
| 25 | 1156001777 |
| 26 | 2754927327 |
| 27 | 6565409092 |
| 28 | 15646364288 |
| 29 | 37287655956 |
| 30 | 88862131873 |
[1,1,2,6,14,33,79,188,448,1068,2545,6065,14454, 34446,82090,195633,466223,1111080,2647872,6310280, 15038353,35838673,85408986,203542550,485072726, 1156001777,2754927327,6565409092,15646364288, 37287655956,88862131873] |