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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 9 |
| 5 | 21 |
| 6 | 56 |
| 7 | 153 |
| 8 | 431 |
| 9 | 1269 |
| 10 | 3748 |
| 11 | 11283 |
| 12 | 34892 |
| 13 | 109201 |
| 14 | 346671 |
| 15 | 1113914 |
| 16 | 3599997 |
| 17 | 11754161 |
| 18 | 38738445 |
| 19 | 128543670 |
| 20 | 429827021 |
| 21 | 1444670782 |
| 22 | 4879545858 |
| 23 | 16575721093 |
| 24 | 56568953256 |
| 25 | 193962159926 |
| 26 | 667744908521 |
| 27 | 2306563486959 |
| 28 | 7996271742308 |
| 29 | 27813368946061 |
| 30 | 97050437964778 |
| 31 | 339653854810804 |
| 32 | 1191781442742137 |
[1,1,2,4,9,21,56,153,431,1269,3748,11283,34892, 109201,346671,1113914,3599997,11754161,38738445, 128543670,429827021,1444670782,4879545858, 16575721093,56568953256,193962159926,667744908521, 2306563486959,7996271742308,27813368946061, 97050437964778,339653854810804,1191781442742137] |