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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 41 |
| 4 | 173 |
| 5 | 759 |
| 6 | 3397 |
| 7 | 15544 |
| 8 | 71901 |
| 9 | 335279 |
| 10 | 1578727 |
| 11 | 7477889 |
| 12 | 35591302 |
| 13 | 170128077 |
| 14 | 816596947 |
| 15 | 3930930312 |
| 16 | 18972648915 |
| 17 | 91803771609 |
| 18 | 445155659067 |
| 19 | 2162359819683 |
| 20 | 10521285811683 |
| 21 | 51271661812391 |
| 22 | 250178483978304 |
| 23 | 1222186872046030 |
| 24 | 5977382665897160 |
| 25 | 29263117871361351 |
| 26 | 143389975617232829 |
[1,3,10,41,173,759,3397,15544,71901,335279, 1578727,7477889,35591302,170128077,816596947, 3930930312,18972648915,91803771609,445155659067, 2162359819683,10521285811683,51271661812391, 250178483978304,1222186872046030,5977382665897160, 29263117871361351,143389975617232829] |