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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 3 |
| 6 | 6 |
| 7 | 10 |
| 8 | 21 |
| 9 | 40 |
| 10 | 85 |
| 11 | 170 |
| 12 | 362 |
| 13 | 752 |
| 14 | 1618 |
| 15 | 3438 |
| 16 | 7447 |
| 17 | 16065 |
| 18 | 35080 |
| 19 | 76574 |
| 20 | 168424 |
| 21 | 370880 |
| 22 | 820968 |
| 23 | 1820598 |
| 24 | 4052594 |
| 25 | 9038457 |
| 26 | 20216002 |
| 27 | 45301380 |
| 28 | 101746560 |
| 29 | 228918438 |
| 30 | 516016266 |
| 31 | 1165005168 |
| 32 | 2634463663 |
| 33 | 5965815375 |
| 34 | 13528669545 |
| 35 | 30717837778 |
[1,1,1,2,3,6,10,21,40,85,170,362,752,1618,3438, 7447,16065,35080,76574,168424,370880,820968, 1820598,4052594,9038457,20216002,45301380, 101746560,228918438,516016266,1165005168, 2634463663,5965815375,13528669545,30717837778] |