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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 14 |
| 5 | 42 |
| 6 | 90 |
| 7 | 200 |
| 8 | 364 |
| 9 | 585 |
| 10 | 960 |
| 11 | 1440 |
| 12 | 2052 |
| 13 | 2926 |
| 14 | 4004 |
| 15 | 5280 |
| 16 | 7000 |
| 17 | 9000 |
| 18 | 11340 |
| 19 | 14280 |
| 20 | 17670 |
| 21 | 21483 |
| 22 | 26180 |
| 23 | 31416 |
| 24 | 37296 |
| 25 | 44252 |
| 26 | 52000 |
| 27 | 60480 |
| 28 | 70434 |
| 29 | 81270 |
| 30 | 93150 |
| 31 | 106720 |
| 32 | 121520 |
| 33 | 137445 |
| 34 | 155584 |
| 35 | 175032 |
| 36 | 196020 |
| 37 | 219450 |
| 38 | 244644 |
| 39 | 271440 |
| 40 | 301340 |
[0,0,0,0,14,42,90,200,364,585,960,1440,2052,2926, 4004,5280,7000,9000,11340,14280,17670,21483,26180, 31416,37296,44252,52000,60480,70434,81270,93150, 106720,121520,137445,155584,175032,196020,219450, 244644,271440,301340] |