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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1028 |
| 3 | 88587 |
| 4 | 2097184 |
| 5 | 24414125 |
| 6 | 181398636 |
| 7 | 988663543 |
| 8 | 4294967552 |
| 9 | 15690530169 |
| 10 | 50000000500 |
| 11 | 142655835971 |
| 12 | 371504186208 |
| 13 | 896080198117 |
| 14 | 2024782586204 |
| 15 | 4324877931375 |
| 16 | 8796093024256 |
| 17 | 17135948156273 |
| 18 | 32134205042532 |
| 19 | 58245129452539 |
| 20 | 102400000004000 |
[0,1,1028,88587,2097184,24414125,181398636, 988663543,4294967552,15690530169,50000000500, 142655835971,371504186208,896080198117, 2024782586204,4324877931375,8796093024256, 17135948156273,32134205042532,58245129452539, 102400000004000] |