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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 4 |
| 5 | 0 |
| 6 | 42 |
| 7 | 0 |
| 8 | 116 |
| 9 | 162 |
| 10 | 730 |
| 11 | 0 |
| 12 | 2458 |
| 13 | 0 |
| 14 | 11494 |
| 15 | 16890 |
| 16 | 32628 |
| 17 | 0 |
| 18 | 180960 |
| 19 | 0 |
| 20 | 554994 |
| 21 | 931476 |
| 22 | 2800534 |
| 23 | 0 |
| 24 | 11005898 |
| 25 | 6643750 |
| 26 | 43946838 |
| 27 | 44738892 |
| 28 | 136580910 |
| 29 | 0 |
| 30 | 720879712 |
| 31 | 0 |
| 32 | 2147450740 |
| 33 | 3250382916 |
| 34 | 10923409738 |
| 35 | 11517062060 |
| 36 | 45683761528 |
| 37 | 0 |
| 38 | 172783692982 |
[0,0,0,4,0,42,0,116,162,730,0,2458,0,11494,16890, 32628,0,180960,0,554994,931476,2800534,0,11005898, 6643750,43946838,44738892,136580910,0,720879712,0, 2147450740,3250382916,10923409738,11517062060, 45683761528,0,172783692982] |