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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 26 |
| 4 | 1089 |
| 5 | 70124 |
| 6 | 6495985 |
| 7 | 821315214 |
| 8 | 136115947009 |
| 9 | 28651724077976 |
| 10 | 7470040450004001 |
| 11 | 2363470644596843330 |
| 12 | 892244303052345224641 |
| 13 | 396227360441775922668036 |
| 14 | 204487588996059177697597969 |
| 15 | 121370399839482643287189048374 |
[1,0,1,26,1089,70124,6495985,821315214, 136115947009,28651724077976,7470040450004001, 2363470644596843330,892244303052345224641, 396227360441775922668036, 204487588996059177697597969, 121370399839482643287189048374] |