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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 13 |
| 5 | 33 |
| 6 | 118 |
| 7 | 347 |
| 8 | 1341 |
| 9 | 4318 |
| 10 | 17545 |
| 11 | 59856 |
| 12 | 251495 |
| 13 | 896183 |
| 14 | 3859528 |
| 15 | 14217556 |
| 16 | 62388697 |
| 17 | 235860592 |
| 18 | 1050383993 |
| 19 | 4055229753 |
| 20 | 18275493427 |
| 21 | 71790138056 |
| 22 | 326702931541 |
| 23 | 1302162074045 |
| 24 | 5974359609738 |
| 25 | 24109258946617 |
| 26 | 111379884904233 |
| 27 | 454295827860432 |
| 28 | 2111201191123406 |
| 29 | 8691686866081354 |
[1,1,2,4,13,33,118,347,1341,4318,17545,59856, 251495,896183,3859528,14217556,62388697,235860592, 1050383993,4055229753,18275493427,71790138056, 326702931541,1302162074045,5974359609738, 24109258946617,111379884904233,454295827860432, 2111201191123406,8691686866081354] |