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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 6 |
| 4 | 18 |
| 5 | 30 |
| 6 | 87 |
| 7 | 200 |
| 8 | 522 |
| 9 | 1421 |
| 10 | 3805 |
| 11 | 10578 |
| 12 | 29465 |
| 13 | 82498 |
| 14 | 232593 |
| 15 | 656577 |
| 16 | 1858073 |
| 17 | 5265011 |
| 18 | 14930674 |
| 19 | 42368708 |
| 20 | 120274026 |
| 21 | 341518697 |
| 22 | 969915776 |
| 23 | 2754886812 |
| 24 | 7825418473 |
| 25 | 22229715609 |
| 26 | 63150286472 |
| 27 | 179401787689 |
| 28 | 509665128216 |
[1,7,6,18,30,87,200,522,1421,3805,10578,29465, 82498,232593,656577,1858073,5265011,14930674, 42368708,120274026,341518697,969915776,2754886812, 7825418473,22229715609,63150286472,179401787689, 509665128216] |