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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 7 |
| 2 | 109 |
| 3 | 2095 |
| 4 | 44401 |
| 5 | 995647 |
| 6 | 23161909 |
| 7 | 552919423 |
| 8 | 13454515585 |
| 9 | 332268466327 |
| 10 | 8302478659069 |
| 11 | 209447296631503 |
| 12 | 5325782947464721 |
| 13 | 136330694520639535 |
| 14 | 3509805380065157989 |
| 15 | 90806156097601965055 |
| 16 | 2359490223343888886785 |
| 17 | 61541525049445532797735 |
| 18 | 1610570872210945422212365 |
[1,7,109,2095,44401,995647,23161909,552919423, 13454515585,332268466327,8302478659069, 209447296631503,5325782947464721, 136330694520639535,3509805380065157989, 90806156097601965055,2359490223343888886785, 61541525049445532797735,1610570872210945422212365] |