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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 13 |
| 5 | 34 |
| 6 | 90 |
| 7 | 243 |
| 8 | 660 |
| 9 | 1818 |
| 10 | 5045 |
| 11 | 14102 |
| 12 | 39639 |
| 13 | 111982 |
| 14 | 317533 |
| 15 | 903464 |
| 16 | 2577724 |
| 17 | 7372542 |
| 18 | 21130127 |
| 19 | 60672017 |
| 20 | 174492633 |
| 21 | 502568607 |
| 22 | 1449360241 |
| 23 | 4184719174 |
| 24 | 12095325486 |
| 25 | 34993693260 |
| 26 | 101332159421 |
| 27 | 293669741860 |
| 28 | 851722291650 |
| 29 | 2471948910379 |
| 30 | 6824540110584 |
[0,1,2,5,13,34,90,243,660,1818,5045,14102,39639, 111982,317533,903464,2577724,7372542,21130127, 60672017,174492633,502568607,1449360241, 4184719174,12095325486,34993693260,101332159421, 293669741860,851722291650,2471948910379, 6824540110584] |