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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 13 |
| 5 | 27 |
| 6 | 54 |
| 7 | 107 |
| 8 | 213 |
| 9 | 423 |
| 10 | 845 |
| 11 | 1685 |
| 12 | 3371 |
| 13 | 6735 |
| 14 | 13468 |
| 15 | 26937 |
| 16 | 53900 |
| 17 | 107873 |
| 18 | 216035 |
| 19 | 432787 |
| 20 | 867313 |
| 21 | 1738728 |
| 22 | 3486464 |
| 23 | 6993111 |
| 24 | 14029776 |
| 25 | 28153533 |
| 26 | 56507114 |
| 27 | 113435141 |
| 28 | 227755613 |
| 29 | 457358671 |
| 30 | 918562597 |
[1,3,6,13,27,54,107,213,423,845,1685,3371,6735, 13468,26937,53900,107873,216035,432787,867313, 1738728,3486464,6993111,14029776,28153533, 56507114,113435141,227755613,457358671,918562597] |