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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 7 |
| 3 | 19 |
| 4 | 45 |
| 5 | 115 |
| 6 | 273 |
| 7 | 683 |
| 8 | 1629 |
| 9 | 4035 |
| 10 | 9643 |
| 11 | 23713 |
| 12 | 56761 |
| 13 | 138883 |
| 14 | 332807 |
| 15 | 811343 |
| 16 | 1945777 |
| 17 | 4730655 |
| 18 | 11351999 |
| 19 | 27542291 |
| 20 | 66123953 |
| 21 | 160174529 |
| 22 | 384700337 |
| 23 | 930720767 |
| 24 | 2236106651 |
| 25 | 5404679299 |
| 26 | 12988762401 |
| 27 | 31370201873 |
| 28 | 75409375419 |
| 29 | 182019777165 |
| 30 | 437648513199 |
[1,3,7,19,45,115,273,683,1629,4035,9643,23713, 56761,138883,332807,811343,1945777,4730655, 11351999,27542291,66123953,160174529,384700337, 930720767,2236106651,5404679299,12988762401, 31370201873,75409375419,182019777165,437648513199] |