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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 6 |
| 4 | 26 |
| 5 | 100 |
| 6 | 1096 |
| 7 | 3920 |
| 8 | 13936 |
| 9 | 16544 |
| 10 | 296256 |
| 11 | 1068672 |
| 12 | 11652352 |
| 13 | 42658304 |
| 14 | 1100471296 |
| 15 | 4079876096 |
| 16 | 15205967872 |
| 17 | 56939270144 |
| 18 | 642281037824 |
| 19 | 2423854317568 |
| 20 | 9177027411968 |
| 21 | 34846713511936 |
| 22 | 1459319692460032 |
| 23 | 5568939824513024 |
| 24 | 21297365878571008 |
[0,1,6,26,100,1096,3920,13936,16544,296256, 1068672,11652352,42658304,1100471296,4079876096, 15205967872,56939270144,642281037824, 2423854317568,9177027411968,34846713511936, 1459319692460032,5568939824513024, 21297365878571008] |