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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 17 |
| 5 | 46 |
| 6 | 153 |
| 7 | 338 |
| 8 | 935 |
| 9 | 3067 |
| 10 | 7182 |
| 11 | 20064 |
| 12 | 64819 |
| 13 | 156968 |
| 14 | 441084 |
| 15 | 1408612 |
| 16 | 3488489 |
| 17 | 9840608 |
| 18 | 31145791 |
| 19 | 78388512 |
| 20 | 221722954 |
| 21 | 696757333 |
| 22 | 1775204952 |
| 23 | 5031253931 |
| 24 | 15718503073 |
| 25 | 40435757688 |
| 26 | 114779701466 |
| 27 | 356852697226 |
| 28 | 925209496348 |
| 29 | 2629513384131 |
[1,1,3,9,17,46,153,338,935,3067,7182,20064,64819, 156968,441084,1408612,3488489,9840608,31145791, 78388512,221722954,696757333,1775204952, 5031253931,15718503073,40435757688,114779701466, 356852697226,925209496348,2629513384131] |