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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 43 |
| 3 | 295 |
| 4 | 1939 |
| 5 | 13139 |
| 6 | 89937 |
| 7 | 619567 |
| 8 | 4214681 |
| 9 | 29077603 |
| 10 | 198628937 |
| 11 | 1373663131 |
| 12 | 9534987699 |
| 13 | 65754164573 |
| 14 | 452049647057 |
| 15 | 3137150763987 |
| 16 | 21650603674011 |
| 17 | 150498748944463 |
| 18 | 1041251352601661 |
| 19 | 7246617431848573 |
| 20 | 50233805965036479 |
[7,43,295,1939,13139,89937,619567,4214681, 29077603,198628937,1373663131,9534987699, 65754164573,452049647057,3137150763987, 21650603674011,150498748944463,1041251352601661, 7246617431848573,50233805965036479] |