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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 12 |
| 5 | 28 |
| 6 | 65 |
| 7 | 151 |
| 8 | 350 |
| 9 | 807 |
| 10 | 1850 |
| 11 | 4221 |
| 12 | 9597 |
| 13 | 21760 |
| 14 | 49215 |
| 15 | 111032 |
| 16 | 249856 |
| 17 | 560835 |
| 18 | 1255854 |
| 19 | 2805969 |
| 20 | 6256784 |
| 21 | 13925698 |
| 22 | 30941050 |
| 23 | 68634679 |
| 24 | 152009239 |
| 25 | 336152787 |
| 26 | 742276931 |
| 27 | 1636747349 |
| 28 | 3604206106 |
| 29 | 7926412320 |
| 30 | 17410413153 |
[1,1,2,5,12,28,65,151,350,807,1850,4221,9597, 21760,49215,111032,249856,560835,1255854,2805969, 6256784,13925698,30941050,68634679,152009239, 336152787,742276931,1636747349,3604206106, 7926412320,17410413153] |