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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 36 |
| 3 | 606 |
| 4 | 4744 |
| 5 | 30850 |
| 6 | 186924 |
| 7 | 1092966 |
| 8 | 6248976 |
| 9 | 35154954 |
| 10 | 195310900 |
| 11 | 1074216814 |
| 12 | 5859372696 |
| 13 | 31738278546 |
| 14 | 170898434364 |
| 15 | 915527340150 |
| 16 | 4882812495904 |
| 17 | 25939941401626 |
| 18 | 137329101557316 |
| 19 | 724792480462974 |
| 20 | 3814697265618600 |
| 21 | 20027160644524194 |
| 22 | 104904174804679756 |
[0,36,606,4744,30850,186924,1092966,6248976, 35154954,195310900,1074216814,5859372696, 31738278546,170898434364,915527340150, 4882812495904,25939941401626,137329101557316, 724792480462974,3814697265618600, 20027160644524194,104904174804679756] |