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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 6 |
| 5 | 12 |
| 6 | 26 |
| 7 | 56 |
| 8 | 124 |
| 9 | 266 |
| 10 | 563 |
| 11 | 1204 |
| 12 | 2573 |
| 13 | 5468 |
| 14 | 11559 |
| 15 | 24370 |
| 16 | 51281 |
| 17 | 107720 |
| 18 | 225867 |
| 19 | 472660 |
| 20 | 987378 |
| 21 | 2059180 |
| 22 | 4287932 |
| 23 | 8916624 |
| 24 | 18517398 |
| 25 | 38406486 |
| 26 | 79563118 |
| 27 | 164636582 |
| 28 | 340308519 |
| 29 | 702713844 |
| 30 | 1449664783 |
| 31 | 2987870476 |
| 32 | 6152930738 |
| 33 | 12660419370 |
| 34 | 26030245642 |
[0,0,1,2,6,12,26,56,124,266,563,1204,2573,5468, 11559,24370,51281,107720,225867,472660,987378, 2059180,4287932,8916624,18517398,38406486, 79563118,164636582,340308519,702713844,1449664783, 2987870476,6152930738,12660419370,26030245642] |