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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 2 |
| 6 | 4 |
| 7 | 2 |
| 8 | 12 |
| 9 | 38 |
| 10 | 60 |
| 11 | 76 |
| 12 | 90 |
| 13 | 480 |
| 14 | 564 |
| 15 | 1232 |
| 16 | 2150 |
| 17 | 2222 |
| 18 | 3156 |
| 19 | 4186 |
| 20 | 4352 |
| 21 | 9616 |
| 22 | 9862 |
| 23 | 11130 |
| 24 | 19848 |
| 25 | 21604 |
| 26 | 23108 |
| 27 | 44394 |
| 28 | 86136 |
| 29 | 110394 |
| 30 | 131936 |
| 31 | 215964 |
| 32 | 756708 |
| 33 | 859296 |
| 34 | 1257648 |
| 35 | 1398120 |
| 36 | 2976070 |
| 37 | 3021220 |
| 38 | 6972430 |
| 39 | 13466750 |
| 40 | 20995838 |
| 41 | 24036404 |
| 42 | 25964770 |
[0,0,0,0,2,4,2,12,38,60,76,90,480,564,1232,2150, 2222,3156,4186,4352,9616,9862,11130,19848,21604, 23108,44394,86136,110394,131936,215964,756708, 859296,1257648,1398120,2976070,3021220,6972430, 13466750,20995838,24036404,25964770] |