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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 10 |
| 5 | 20 |
| 6 | 48 |
| 7 | 120 |
| 8 | 320 |
| 9 | 640 |
| 10 | 1520 |
| 11 | 3648 |
| 12 | 9216 |
| 13 | 23040 |
| 14 | 59520 |
| 15 | 158720 |
| 16 | 426240 |
| 17 | 852480 |
| 18 | 2037760 |
| 19 | 4839680 |
| 20 | 12038400 |
| 21 | 28892160 |
| 22 | 72142848 |
| 23 | 182255616 |
| 24 | 464781312 |
| 25 | 1161953280 |
| 26 | 2957967360 |
| 27 | 7641415680 |
| 28 | 19777781760 |
| 29 | 52740751360 |
| 30 | 138779688960 |
| 31 | 372690616320 |
| 32 | 990786355200 |
| 33 | 1981572710400 |
| 34 | 4793092669440 |
| 35 | 11457362657280 |
| 36 | 28548724162560 |
[1,1,2,4,10,20,48,120,320,640,1520,3648,9216, 23040,59520,158720,426240,852480,2037760,4839680, 12038400,28892160,72142848,182255616,464781312, 1161953280,2957967360,7641415680,19777781760, 52740751360,138779688960,372690616320, 990786355200,1981572710400,4793092669440, 11457362657280,28548724162560] |