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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 4 |
| 5 | 6 |
| 6 | 14 |
| 7 | 26 |
| 8 | 49 |
| 9 | 78 |
| 10 | 181 |
| 11 | 360 |
| 12 | 717 |
| 13 | 1414 |
| 14 | 2776 |
| 15 | 5270 |
| 16 | 9486 |
| 17 | 15116 |
| 18 | 35501 |
| 19 | 71000 |
| 20 | 141997 |
| 21 | 283974 |
| 22 | 567896 |
| 23 | 1135510 |
| 24 | 2269966 |
| 25 | 4536076 |
| 26 | 9062306 |
| 27 | 18068728 |
| 28 | 35924482 |
| 29 | 70997428 |
| 30 | 138594290 |
| 31 | 263655928 |
| 32 | 474383156 |
| 33 | 756107812 |
[1,1,3,4,6,14,26,49,78,181,360,717,1414,2776,5270, 9486,15116,35501,71000,141997,283974,567896, 1135510,2269966,4536076,9062306,18068728,35924482, 70997428,138594290,263655928,474383156,756107812] |