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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 12 |
| 5 | 25 |
| 6 | 87 |
| 7 | 189 |
| 8 | 844 |
| 9 | 2061 |
| 10 | 8265 |
| 11 | 20317 |
| 12 | 94014 |
| 13 | 246389 |
| 14 | 1051736 |
| 15 | 2752635 |
| 16 | 12971752 |
| 17 | 35409589 |
| 18 | 156545721 |
| 19 | 425681757 |
| 20 | 2028643354 |
| 21 | 5687451021 |
| 22 | 25714495202 |
| 23 | 71753924987 |
| 24 | 344569097136 |
| 25 | 984453928825 |
| 26 | 4520756671327 |
| 27 | 12852585508149 |
| 28 | 62061211995954 |
| 29 | 179832324062041 |
| 30 | 835295154466845 |
| 31 | 2408594166730577 |
[1,1,2,3,12,25,87,189,844,2061,8265,20317,94014, 246389,1051736,2752635,12971752,35409589, 156545721,425681757,2028643354,5687451021, 25714495202,71753924987,344569097136,984453928825, 4520756671327,12852585508149,62061211995954, 179832324062041,835295154466845,2408594166730577] |