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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 13 |
| 2 | 0 |
| 3 | 1164 |
| 4 | 15132 |
| 5 | 230484 |
| 6 | 2823492 |
| 7 | 36705396 |
| 8 | 508541124 |
| 9 | 7194470556 |
| 10 | 100696385244 |
| 11 | 1503091145388 |
| 12 | 19540184890044 |
| 13 | 273550891167372 |
| 14 | 3811871194625676 |
| 15 | 53378900339114532 |
| 16 | 727176010568075796 |
| 17 | 10177815744800162004 |
| 18 | 142523339476298463228 |
| 19 | 1994910930816765350844 |
| 20 | 27918212600229725023068 |
[1,13,0,1164,15132,230484,2823492,36705396, 508541124,7194470556,100696385244,1503091145388, 19540184890044,273550891167372,3811871194625676, 53378900339114532,727176010568075796, 10177815744800162004,142523339476298463228, 1994910930816765350844,27918212600229725023068] |