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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 137225 |
| 5 | 7231840 |
| 6 | 511741475 |
| 7 | 20997046400 |
| 8 | 642104180575 |
| 9 | 14620696059200 |
| 10 | 255580729090995 |
| 11 | 3496191224323200 |
| 12 | 38040223036760175 |
| 13 | 333583215539666400 |
| 14 | 2383620193904285325 |
| 15 | 14005823013894187520 |
| 16 | 68193674589734420650 |
| 17 | 276907649362395385600 |
| 18 | 942804613467381809925 |
| 19 | 2703690046024936460800 |
| 20 | 6554715226694274576090 |
| 21 | 13474850114631510264000 |
| 22 | 23545377636355278743550 |
| 23 | 35033701987289528723200 |
| 24 | 44444350658167367673150 |
| 25 | 48108742023087188141952 |
[1,0,0,0,137225,7231840,511741475,20997046400, 642104180575,14620696059200,255580729090995, 3496191224323200,38040223036760175, 333583215539666400,2383620193904285325, 14005823013894187520,68193674589734420650, 276907649362395385600,942804613467381809925, 2703690046024936460800,6554715226694274576090, 13474850114631510264000,23545377636355278743550, 35033701987289528723200,44444350658167367673150, 48108742023087188141952] |