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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 3 |
| 6 | 16 |
| 7 | 24 |
| 8 | 98 |
| 9 | 161 |
| 10 | 515 |
| 11 | 956 |
| 12 | 2641 |
| 13 | 5686 |
| 14 | 14869 |
| 15 | 33986 |
| 16 | 84574 |
| 17 | 196092 |
| 18 | 474284 |
| 19 | 1110888 |
| 20 | 2665506 |
| 21 | 6280574 |
| 22 | 15027417 |
| 23 | 35701279 |
| 24 | 85266546 |
| 25 | 202157753 |
| 26 | 480306818 |
| 27 | 1140496671 |
| 28 | 2711160051 |
| 29 | 6442522473 |
| 30 | 15326524978 |
| 31 | 36425732326 |
[0,1,1,3,3,16,24,98,161,515,956,2641,5686,14869, 33986,84574,196092,474284,1110888,2665506,6280574, 15027417,35701279,85266546,202157753,480306818, 1140496671,2711160051,6442522473,15326524978, 36425732326] |