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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 35 |
| 3 | 181 |
| 4 | 953 |
| 5 | 4997 |
| 6 | 26155 |
| 7 | 137033 |
| 8 | 717905 |
| 9 | 3760657 |
| 10 | 19700359 |
| 11 | 103201589 |
| 12 | 540625665 |
| 13 | 2832090849 |
| 14 | 14836035579 |
| 15 | 77719229889 |
| 16 | 407135626281 |
| 17 | 2132798039801 |
| 18 | 11172757117047 |
| 19 | 58528983567693 |
| 20 | 306606675825193 |
| 21 | 1606172667510097 |
[7,35,181,953,4997,26155,137033,717905,3760657, 19700359,103201589,540625665,2832090849, 14836035579,77719229889,407135626281, 2132798039801,11172757117047,58528983567693, 306606675825193,1606172667510097] |