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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 8 |
| 7 | 38 |
| 8 | 194 |
| 9 | 1138 |
| 10 | 8154 |
| 11 | 71544 |
| 12 | 739406 |
| 13 | 8674238 |
| 14 | 113451160 |
| 15 | 1648133190 |
| 16 | 26631054962 |
| 17 | 478633871152 |
| 18 | 9531297220728 |
| 19 | 208851860234540 |
| 20 | 4997665703050398 |
| 21 | 129765874491438094 |
| 22 | 3639593254921626678 |
| 23 | 109942671192206473592 |
| 24 | 3569449102675488493032 |
| 25 | 124319448405579907085938 |
[0,1,0,1,1,2,8,38,194,1138,8154,71544,739406, 8674238,113451160,1648133190,26631054962, 478633871152,9531297220728,208851860234540, 4997665703050398,129765874491438094, 3639593254921626678,109942671192206473592, 3569449102675488493032,124319448405579907085938] |