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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 9 |
| 5 | 21 |
| 6 | 43 |
| 7 | 92 |
| 8 | 196 |
| 9 | 414 |
| 10 | 882 |
| 11 | 1869 |
| 12 | 3970 |
| 13 | 8427 |
| 14 | 17887 |
| 15 | 37975 |
| 16 | 80608 |
| 17 | 171121 |
| 18 | 363254 |
| 19 | 771119 |
| 20 | 1636944 |
| 21 | 3474913 |
| 22 | 7376591 |
| 23 | 15659094 |
| 24 | 33241289 |
| 25 | 70564951 |
| 26 | 149795989 |
| 27 | 317988473 |
| 28 | 675029164 |
| 29 | 1432958824 |
| 30 | 3041899638 |
| 31 | 6457375642 |
| 32 | 13707783053 |
| 33 | 29099021980 |
[1,1,2,5,9,21,43,92,196,414,882,1869,3970,8427, 17887,37975,80608,171121,363254,771119,1636944, 3474913,7376591,15659094,33241289,70564951, 149795989,317988473,675029164,1432958824, 3041899638,6457375642,13707783053,29099021980] |