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| n | a(n) |
|---|---|
| 3 | 0 |
| 4 | 2 |
| 5 | 2 |
| 6 | 2 |
| 7 | 11 |
| 8 | 14 |
| 9 | 40 |
| 10 | 95 |
| 11 | 219 |
| 12 | 533 |
| 13 | 1345 |
| 14 | 3069 |
| 15 | 7761 |
| 16 | 20001 |
| 17 | 49779 |
| 18 | 130008 |
| 19 | 334948 |
| 20 | 860761 |
| 21 | 2238582 |
| 22 | 5814567 |
| 23 | 15150352 |
| 24 | 39701964 |
| 25 | 104297006 |
| 26 | 274773655 |
| 27 | 726702936 |
| 28 | 1925437370 |
| 29 | 5114308676 |
| 30 | 13616020075 |
| 31 | 36311313036 |
[0,2,2,2,11,14,40,95,219,533,1345,3069,7761,20001, 49779,130008,334948,860761,2238582,5814567, 15150352,39701964,104297006,274773655,726702936, 1925437370,5114308676,13616020075,36311313036] |