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| n | a(n) |
|---|---|
| 3 | 0 |
| 4 | 1 |
| 5 | 3 |
| 6 | 3 |
| 7 | 13 |
| 8 | 30 |
| 9 | 41 |
| 10 | 136 |
| 11 | 335 |
| 12 | 566 |
| 13 | 1559 |
| 14 | 3919 |
| 15 | 8386 |
| 16 | 21334 |
| 17 | 54333 |
| 18 | 129669 |
| 19 | 327306 |
| 20 | 849762 |
| 21 | 2164290 |
| 22 | 5588388 |
| 23 | 14709540 |
| 24 | 38681879 |
| 25 | 101992196 |
| 26 | 271155602 |
| 27 | 722264852 |
| 28 | 1924729081 |
| 29 | 5143690028 |
| 30 | 13762710938 |
| 31 | 36830667724 |
[0,1,3,3,13,30,41,136,335,566,1559,3919,8386, 21334,54333,129669,327306,849762,2164290,5588388, 14709540,38681879,101992196,271155602,722264852, 1924729081,5143690028,13762710938,36830667724] |