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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 43 |
| 3 | 257 |
| 4 | 1693 |
| 5 | 10997 |
| 6 | 74255 |
| 7 | 492758 |
| 8 | 3349106 |
| 9 | 22433886 |
| 10 | 152643539 |
| 11 | 1027272805 |
| 12 | 6985683412 |
| 13 | 47128486230 |
| 14 | 320193692690 |
| 15 | 2163219506254 |
| 16 | 14685211888947 |
| 17 | 99300200123859 |
| 18 | 673693197611946 |
| 19 | 4558092645337083 |
| 20 | 30910190288935629 |
[7,43,257,1693,10997,74255,492758,3349106, 22433886,152643539,1027272805,6985683412, 47128486230,320193692690,2163219506254, 14685211888947,99300200123859,673693197611946, 4558092645337083,30910190288935629] |