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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 10 |
| 3 | 64 |
| 4 | 512 |
| 5 | 4768 |
| 6 | 53056 |
| 7 | 645440 |
| 8 | 8868352 |
| 9 | 133302016 |
| 10 | 2184149504 |
| 11 | 38530160128 |
| 12 | 733246566400 |
| 13 | 14834910150656 |
| 14 | 319778313883648 |
| 15 | 7292507623063552 |
| 16 | 175517505539538944 |
| 17 | 4440588163825008640 |
| 18 | 117969026857318678528 |
| 19 | 3276703253565946855424 |
| 20 | 95086071773832697348096 |
[1,2,10,64,512,4768,53056,645440,8868352, 133302016,2184149504,38530160128,733246566400, 14834910150656,319778313883648,7292507623063552, 175517505539538944,4440588163825008640, 117969026857318678528,3276703253565946855424, 95086071773832697348096] |