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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 9 |
| 3 | 14 |
| 4 | 24 |
| 5 | 42 |
| 6 | 77 |
| 7 | 144 |
| 8 | 276 |
| 9 | 538 |
| 10 | 1065 |
| 11 | 2136 |
| 12 | 4321 |
| 13 | 8790 |
| 14 | 17967 |
| 15 | 36890 |
| 16 | 76050 |
| 17 | 157380 |
| 18 | 326824 |
| 19 | 680880 |
| 20 | 1422570 |
| 21 | 2979572 |
| 22 | 6254175 |
| 23 | 13153242 |
| 24 | 27712901 |
| 25 | 58487796 |
| 26 | 123632910 |
| 27 | 261722022 |
| 28 | 554800719 |
| 29 | 1177553610 |
| 30 | 2502256578 |
| 31 | 5322993522 |
[6,9,14,24,42,77,144,276,538,1065,2136,4321,8790, 17967,36890,76050,157380,326824,680880,1422570, 2979572,6254175,13153242,27712901,58487796, 123632910,261722022,554800719,1177553610, 2502256578,5322993522] |