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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 6 |
| 5 | 15 |
| 6 | 31 |
| 7 | 74 |
| 8 | 159 |
| 9 | 365 |
| 10 | 805 |
| 11 | 1819 |
| 12 | 4041 |
| 13 | 9091 |
| 14 | 20274 |
| 15 | 45474 |
| 16 | 101644 |
| 17 | 227755 |
| 18 | 509559 |
| 19 | 1141446 |
| 20 | 2555232 |
| 21 | 5723626 |
| 22 | 12817678 |
| 23 | 28713594 |
| 24 | 64319189 |
| 25 | 144104857 |
| 26 | 322867573 |
| 27 | 723482538 |
| 28 | 1621264326 |
| 29 | 3633487621 |
| 30 | 8143682973 |
| 31 | 18253865341 |
| 32 | 40918282628 |
| 33 | 91730206467 |
[0,1,1,3,6,15,31,74,159,365,805,1819,4041,9091, 20274,45474,101644,227755,509559,1141446,2555232, 5723626,12817678,28713594,64319189,144104857, 322867573,723482538,1621264326,3633487621, 8143682973,18253865341,40918282628,91730206467] |