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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 2 |
| 3 | 3 |
| 4 | 5 |
| 5 | 9 |
| 6 | 20 |
| 7 | 44 |
| 8 | 102 |
| 9 | 243 |
| 10 | 590 |
| 11 | 1464 |
| 12 | 3690 |
| 13 | 9433 |
| 14 | 24402 |
| 15 | 63772 |
| 16 | 168151 |
| 17 | 446851 |
| 18 | 1195742 |
| 19 | 3219560 |
| 20 | 8716961 |
| 21 | 23719621 |
| 22 | 64836900 |
| 23 | 177964421 |
| 24 | 490329056 |
| 25 | 1355661775 |
| 26 | 3760156550 |
| 27 | 10460353203 |
| 28 | 29179582212 |
| 29 | 81605680576 |
| 30 | 228767924549 |
| 31 | 642740266684 |
| 32 | 1809590028175 |
[3,2,3,5,9,20,44,102,243,590,1464,3690,9433,24402, 63772,168151,446851,1195742,3219560,8716961, 23719621,64836900,177964421,490329056,1355661775, 3760156550,10460353203,29179582212,81605680576, 228767924549,642740266684,1809590028175] |