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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 5 |
| 4 | 19 |
| 5 | 389 |
| 6 | 1045 |
| 7 | 78077 |
| 8 | 623245 |
| 9 | 6626426 |
| 10 | 3301971 |
| 11 | 92695530505 |
| 12 | 285361879 |
| 13 | 17061288862565 |
| 14 | 1065000744223 |
| 15 | 25118392969537 |
| 16 | 2119645764556535 |
| 17 | 147712619442026368532 |
| 18 | 1188946883458975 |
| 19 | 240322519506608309910831 |
| 20 | 9412105864959423959 |
| 21 | 3368266474732313495945 |
| 22 | 29482240157146090479193 |
[0,1,5,19,389,1045,78077,623245,6626426,3301971, 92695530505,285361879,17061288862565, 1065000744223,25118392969537,2119645764556535, 147712619442026368532,1188946883458975, 240322519506608309910831,9412105864959423959, 3368266474732313495945,29482240157146090479193] |