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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 35 |
| 4 | 153 |
| 5 | 673 |
| 6 | 3056 |
| 7 | 13961 |
| 8 | 64691 |
| 9 | 302034 |
| 10 | 1419777 |
| 11 | 6707589 |
| 12 | 31848340 |
| 13 | 151777512 |
| 14 | 725705977 |
| 15 | 3479885667 |
| 16 | 16729718128 |
| 17 | 80604358661 |
| 18 | 389127748054 |
| 19 | 1881938427809 |
| 20 | 9116193100734 |
| 21 | 44223103712110 |
| 22 | 214814131463072 |
| 23 | 1044728780081191 |
| 24 | 5086579661859410 |
| 25 | 24790977087846770 |
| 26 | 120941239005789793 |
[1,2,9,35,153,673,3056,13961,64691,302034,1419777, 6707589,31848340,151777512,725705977,3479885667, 16729718128,80604358661,389127748054, 1881938427809,9116193100734,44223103712110, 214814131463072,1044728780081191,5086579661859410, 24790977087846770,120941239005789793] |