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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 6 |
| 6 | 12 |
| 7 | 28 |
| 8 | 65 |
| 9 | 166 |
| 10 | 412 |
| 11 | 1076 |
| 12 | 2806 |
| 13 | 7524 |
| 14 | 20020 |
| 15 | 54744 |
| 16 | 148417 |
| 17 | 410078 |
| 18 | 1126732 |
| 19 | 3144500 |
| 20 | 8728570 |
| 21 | 24555900 |
| 22 | 68713420 |
| 23 | 194469616 |
| 24 | 548088278 |
| 25 | 1559301428 |
| 26 | 4418131108 |
| 27 | 12628267512 |
| 28 | 35957541462 |
| 29 | 103150588492 |
| 30 | 294924202032 |
| 31 | 848878072440 |
| 32 | 2435729999665 |
[1,1,2,3,6,12,28,65,166,412,1076,2806,7524,20020, 54744,148417,410078,1126732,3144500,8728570, 24555900,68713420,194469616,548088278,1559301428, 4418131108,12628267512,35957541462,103150588492, 294924202032,848878072440,2435729999665] |