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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 17 |
| 5 | 49 |
| 6 | 135 |
| 7 | 380 |
| 8 | 1051 |
| 9 | 2925 |
| 10 | 8119 |
| 11 | 22548 |
| 12 | 62574 |
| 13 | 173767 |
| 14 | 482360 |
| 15 | 1339126 |
| 16 | 3717700 |
| 17 | 10321163 |
| 18 | 28653557 |
| 19 | 79548612 |
| 20 | 220843925 |
| 21 | 613110573 |
| 22 | 1702128034 |
| 23 | 4725475979 |
| 24 | 13118945083 |
| 25 | 36421037100 |
| 26 | 101112695940 |
| 27 | 280710759278 |
| 28 | 779313926949 |
| 29 | 2163544401343 |
| 30 | 6006468273440 |
[1,1,2,6,17,49,135,380,1051,2925,8119,22548,62574, 173767,482360,1339126,3717700,10321163,28653557, 79548612,220843925,613110573,1702128034, 4725475979,13118945083,36421037100,101112695940, 280710759278,779313926949,2163544401343, 6006468273440] |