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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 4 |
| 5 | 11 |
| 6 | 41 |
| 7 | 162 |
| 8 | 715 |
| 9 | 3425 |
| 10 | 16777 |
| 11 | 80928 |
| 12 | 379347 |
| 13 | 1726375 |
| 14 | 7654817 |
| 15 | 33219630 |
| 16 | 141692075 |
| 17 | 596122477 |
| 18 | 2480969257 |
| 19 | 10237751324 |
| 20 | 41963944275 |
| 21 | 171103765747 |
| 22 | 694775280993 |
| 23 | 2812004330666 |
| 24 | 11352134320523 |
| 25 | 45736973060601 |
| 26 | 183981143571721 |
| 27 | 739167464021912 |
| 28 | 2966826380664595 |
| 29 | 11899055223201855 |
[0,0,1,1,4,11,41,162,715,3425,16777,80928,379347, 1726375,7654817,33219630,141692075,596122477, 2480969257,10237751324,41963944275,171103765747, 694775280993,2812004330666,11352134320523, 45736973060601,183981143571721,739167464021912, 2966826380664595,11899055223201855] |