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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 2 |
| 3 | 24 |
| 4 | 68 |
| 5 | 364 |
| 6 | 504 |
| 7 | 2040 |
| 8 | 3606 |
| 9 | 7664 |
| 10 | 10422 |
| 11 | 25764 |
| 12 | 34226 |
| 13 | 70836 |
| 14 | 89994 |
| 15 | 128532 |
| 16 | 177276 |
| 17 | 316844 |
| 18 | 375952 |
| 19 | 623024 |
| 20 | 757604 |
| 21 | 986742 |
| 22 | 1188760 |
| 23 | 1828860 |
| 24 | 2093672 |
| 25 | 2885342 |
| 26 | 3379568 |
| 27 | 4347890 |
| 28 | 5089220 |
| 29 | 7134860 |
| 30 | 7835684 |
| 31 | 10700654 |
| 32 | 12422758 |
| 33 | 14837078 |
| 34 | 16812466 |
| 35 | 20404320 |
[0,2,24,68,364,504,2040,3606,7664,10422,25764, 34226,70836,89994,128532,177276,316844,375952, 623024,757604,986742,1188760,1828860,2093672, 2885342,3379568,4347890,5089220,7134860,7835684, 10700654,12422758,14837078,16812466,20404320] |