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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 13 |
| 4 | 55 |
| 5 | 183 |
| 6 | 819 |
| 7 | 2879 |
| 8 | 13213 |
| 9 | 49231 |
| 10 | 227123 |
| 11 | 876693 |
| 12 | 4073717 |
| 13 | 16120745 |
| 14 | 75276547 |
| 15 | 303636677 |
| 16 | 1423564969 |
| 17 | 5828509759 |
| 18 | 27410607645 |
| 19 | 113608901595 |
| 20 | 535627472609 |
| 21 | 2242499571405 |
| 22 | 10595328825363 |
| 23 | 44737401067095 |
| 24 | 211764340741683 |
| 25 | 900663481977615 |
| 26 | 4270082893059887 |
| 27 | 18275969442297959 |
[1,1,5,13,55,183,819,2879,13213,49231,227123, 876693,4073717,16120745,75276547,303636677, 1423564969,5828509759,27410607645,113608901595, 535627472609,2242499571405,10595328825363, 44737401067095,211764340741683,900663481977615, 4270082893059887,18275969442297959] |