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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 4 |
| 5 | 1 |
| 6 | 6 |
| 7 | 1 |
| 8 | 64 |
| 9 | 505 |
| 10 | 130 |
| 11 | 1321 |
| 12 | 1024 |
| 13 | 13157 |
| 14 | 2380 |
| 15 | 395851 |
| 16 | 5782144 |
| 17 | 1639617 |
| 18 | 24545706 |
| 19 | 16100905 |
| 20 | 306621184 |
| 21 | 292018525 |
| 22 | 6304002100 |
| 23 | 1549052715 |
| 24 | 507969498304 |
| 25 | 11794047630801 |
| 26 | 3164830777316 |
| 27 | 75389026652551 |
| 28 | 48756350408224 |
| 29 | 1240389053007865 |
[1,1,0,1,4,1,6,1,64,505,130,1321,1024,13157,2380, 395851,5782144,1639617,24545706,16100905, 306621184,292018525,6304002100,1549052715, 507969498304,11794047630801,3164830777316, 75389026652551,48756350408224,1240389053007865] |