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| n | a(n) |
|---|---|
| 3 | 0 |
| 4 | 0 |
| 5 | 4 |
| 6 | 3 |
| 7 | 2 |
| 8 | 26 |
| 9 | 38 |
| 10 | 62 |
| 11 | 242 |
| 12 | 558 |
| 13 | 1202 |
| 14 | 3340 |
| 15 | 8696 |
| 16 | 21250 |
| 17 | 54336 |
| 18 | 141989 |
| 19 | 363816 |
| 20 | 934293 |
| 21 | 2445407 |
| 22 | 6400169 |
| 23 | 16733638 |
| 24 | 44132199 |
| 25 | 116636298 |
| 26 | 308224217 |
| 27 | 817910147 |
| 28 | 2174929052 |
| 29 | 5787607643 |
| 30 | 15438812813 |
| 31 | 41263843971 |
[0,0,4,3,2,26,38,62,242,558,1202,3340,8696,21250, 54336,141989,363816,934293,2445407,6400169, 16733638,44132199,116636298,308224217,817910147, 2174929052,5787607643,15438812813,41263843971] |