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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 10 |
| 5 | 22 |
| 6 | 40 |
| 7 | 70 |
| 8 | 133 |
| 9 | 254 |
| 10 | 482 |
| 11 | 902 |
| 12 | 1710 |
| 13 | 3214 |
| 14 | 6094 |
| 15 | 11446 |
| 16 | 21702 |
| 17 | 40766 |
| 18 | 77294 |
| 19 | 145190 |
| 20 | 275286 |
| 21 | 517102 |
| 22 | 980446 |
| 23 | 1841686 |
| 24 | 3491910 |
| 25 | 6559262 |
| 26 | 12436622 |
| 27 | 23361158 |
| 28 | 44293686 |
| 29 | 83201998 |
| 30 | 157754302 |
| 31 | 296328310 |
| 32 | 561850278 |
| 33 | 1055388926 |
[1,2,4,10,22,40,70,133,254,482,902,1710,3214,6094, 11446,21702,40766,77294,145190,275286,517102, 980446,1841686,3491910,6559262,12436622,23361158, 44293686,83201998,157754302,296328310,561850278, 1055388926] |