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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 1 |
| 3 | 7 |
| 4 | 25 |
| 5 | 15 |
| 6 | 49 |
| 7 | 151 |
| 8 | 505 |
| 9 | 15 |
| 10 | 881 |
| 11 | 2327 |
| 12 | 7545 |
| 13 | 1807 |
| 14 | 12657 |
| 15 | 38167 |
| 16 | 122745 |
| 17 | 17295 |
| 18 | 252145 |
| 19 | 588567 |
| 20 | 1969017 |
| 21 | 502031 |
| 22 | 3735409 |
| 23 | 10158871 |
| 24 | 32094585 |
| 25 | 7118223 |
| 26 | 61269745 |
| 27 | 150108951 |
| 28 | 505383801 |
| 29 | 46246159 |
| 30 | 1047330673 |
| 31 | 2269053719 |
| 32 | 7273036153 |
| 33 | 6928375183 |
[1,3,1,7,25,15,49,151,505,15,881,2327,7545,1807, 12657,38167,122745,17295,252145,588567,1969017, 502031,3735409,10158871,32094585,7118223,61269745, 150108951,505383801,46246159,1047330673, 2269053719,7273036153,6928375183] |