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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 5 |
| 6 | 19 |
| 7 | 82 |
| 8 | 324 |
| 9 | 1328 |
| 10 | 5367 |
| 11 | 21809 |
| 12 | 88463 |
| 13 | 359056 |
| 14 | 1457052 |
| 15 | 5913112 |
| 16 | 23996513 |
| 17 | 97382945 |
| 18 | 395199883 |
| 19 | 1603802802 |
| 20 | 6508562056 |
| 21 | 26413086624 |
| 22 | 107189749111 |
| 23 | 434998095205 |
| 24 | 1765311927087 |
| 25 | 7163999648656 |
| 26 | 29072987143064 |
| 27 | 117984174051328 |
| 28 | 478804095978481 |
| 29 | 1943085707636701 |
| 30 | 7885442290344115 |
[0,0,0,1,5,19,82,324,1328,5367,21809,88463,359056, 1457052,5913112,23996513,97382945,395199883, 1603802802,6508562056,26413086624,107189749111, 434998095205,1765311927087,7163999648656, 29072987143064,117984174051328,478804095978481, 1943085707636701,7885442290344115] |