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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 9 |
| 3 | 23 |
| 4 | 52 |
| 5 | 110 |
| 6 | 231 |
| 7 | 472 |
| 8 | 965 |
| 9 | 1958 |
| 10 | 3962 |
| 11 | 7980 |
| 12 | 16029 |
| 13 | 32181 |
| 14 | 64597 |
| 15 | 129574 |
| 16 | 259798 |
| 17 | 520835 |
| 18 | 1043833 |
| 19 | 2091473 |
| 20 | 4190135 |
| 21 | 8392863 |
| 22 | 16809322 |
| 23 | 33661860 |
| 24 | 67402676 |
| 25 | 134952624 |
| 26 | 270177158 |
| 27 | 540861852 |
| 28 | 1082667610 |
| 29 | 2167106199 |
| 30 | 4337519113 |
| 31 | 8681255531 |
| 32 | 17374202846 |
| 33 | 34770433922 |
| 34 | 69582458821 |
| 35 | 139243546013 |
| 36 | 278635987083 |
[2,9,23,52,110,231,472,965,1958,3962,7980,16029, 32181,64597,129574,259798,520835,1043833,2091473, 4190135,8392863,16809322,33661860,67402676, 134952624,270177158,540861852,1082667610, 2167106199,4337519113,8681255531,17374202846, 34770433922,69582458821,139243546013,278635987083] |