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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 16 |
| 8 | 148 |
| 9 | 756 |
| 10 | 2820 |
| 11 | 8580 |
| 12 | 22572 |
| 13 | 53224 |
| 14 | 115036 |
| 15 | 231960 |
| 16 | 441032 |
| 17 | 799064 |
| 18 | 1387368 |
| 19 | 2324744 |
| 20 | 3771176 |
| 21 | 5952528 |
| 22 | 9159392 |
| 23 | 13791008 |
| 24 | 20340036 |
| 25 | 29476508 |
| 26 | 41992820 |
| 27 | 58953420 |
| 28 | 81591788 |
| 29 | 111535064 |
| 30 | 150611100 |
| 31 | 201257608 |
[0,0,0,0,0,0,16,148,756,2820,8580,22572,53224, 115036,231960,441032,799064,1387368,2324744, 3771176,5952528,9159392,13791008,20340036, 29476508,41992820,58953420,81591788,111535064, 150611100,201257608] |