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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 8 |
| 5 | 15 |
| 6 | 30 |
| 7 | 56 |
| 8 | 107 |
| 9 | 200 |
| 10 | 372 |
| 11 | 680 |
| 12 | 1241 |
| 13 | 2221 |
| 14 | 3938 |
| 15 | 6880 |
| 16 | 11860 |
| 17 | 20148 |
| 18 | 33778 |
| 19 | 55814 |
| 20 | 91007 |
| 21 | 146392 |
| 22 | 232458 |
| 23 | 364462 |
| 24 | 564560 |
| 25 | 864230 |
| 26 | 1308160 |
| 27 | 1958700 |
| 28 | 2902417 |
| 29 | 4258009 |
| 30 | 6187350 |
| 31 | 8908680 |
| 32 | 12714829 |
| 33 | 17994860 |
| 34 | 25262928 |
| 35 | 35193094 |
| 36 | 48664341 |
| 37 | 66814595 |
| 38 | 91109910 |
| 39 | 123426848 |
| 40 | 166156091 |
[1,2,4,8,15,30,56,107,200,372,680,1241,2221,3938, 6880,11860,20148,33778,55814,91007,146392,232458, 364462,564560,864230,1308160,1958700,2902417, 4258009,6187350,8908680,12714829,17994860, 25262928,35193094,48664341,66814595,91109910, 123426848,166156091] |