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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 7 |
| 3 | 35 |
| 4 | 156 |
| 5 | 660 |
| 6 | 2717 |
| 7 | 11011 |
| 8 | 44200 |
| 9 | 176358 |
| 10 | 700910 |
| 11 | 2778446 |
| 12 | 10994920 |
| 13 | 43459650 |
| 14 | 171655785 |
| 15 | 677688675 |
| 16 | 2674776720 |
| 17 | 10555815270 |
| 18 | 41656918050 |
| 19 | 164401379610 |
| 20 | 648887951400 |
| 21 | 2561511781920 |
| 22 | 10113397410402 |
| 23 | 39937416869070 |
| 24 | 157743149913776 |
| 25 | 623178050662300 |
[0,1,7,35,156,660,2717,11011,44200,176358,700910, 2778446,10994920,43459650,171655785,677688675, 2674776720,10555815270,41656918050,164401379610, 648887951400,2561511781920,10113397410402, 39937416869070,157743149913776,623178050662300] |