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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 2 |
| 7 | 28 |
| 8 | 144 |
| 9 | 292 |
| 10 | 272 |
| 11 | 160 |
| 12 | 272 |
| 13 | 844 |
| 14 | 3888 |
| 15 | 15830 |
| 16 | 49080 |
| 17 | 113468 |
| 18 | 208224 |
| 19 | 352112 |
| 20 | 662810 |
| 21 | 1497286 |
| 22 | 3853054 |
| 23 | 10238142 |
| 24 | 25892602 |
| 25 | 60223752 |
| 26 | 130042700 |
| 27 | 271136524 |
| 28 | 572265830 |
| 29 | 1258121046 |
| 30 | 2878870324 |
| 31 | 6714840216 |
| 32 | 15583281118 |
| 33 | 35434903508 |
| 34 | 78777769972 |
| 35 | 172664047056 |
[1,0,0,0,0,2,28,144,292,272,160,272,844,3888, 15830,49080,113468,208224,352112,662810,1497286, 3853054,10238142,25892602,60223752,130042700, 271136524,572265830,1258121046,2878870324, 6714840216,15583281118,35434903508,78777769972, 172664047056] |