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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 11 |
| 3 | 15 |
| 4 | 33 |
| 5 | 117 |
| 6 | 247 |
| 7 | 599 |
| 8 | 1757 |
| 9 | 4241 |
| 10 | 10783 |
| 11 | 29239 |
| 12 | 74521 |
| 13 | 192273 |
| 14 | 508375 |
| 15 | 1317567 |
| 16 | 3422449 |
| 17 | 8971629 |
| 18 | 23370303 |
| 19 | 60880867 |
| 20 | 159136445 |
| 21 | 415145389 |
| 22 | 1082772235 |
| 23 | 2827552935 |
| 24 | 7379387077 |
| 25 | 19255943685 |
| 26 | 50269166119 |
| 27 | 131207698359 |
[1,11,15,33,117,247,599,1757,4241,10783,29239, 74521,192273,508375,1317567,3422449,8971629, 23370303,60880867,159136445,415145389,1082772235, 2827552935,7379387077,19255943685,50269166119, 131207698359] |