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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 11 |
| 3 | 30 |
| 4 | 81 |
| 5 | 198 |
| 6 | 477 |
| 7 | 1089 |
| 8 | 2451 |
| 9 | 5358 |
| 10 | 11567 |
| 11 | 24537 |
| 12 | 51577 |
| 13 | 107205 |
| 14 | 221378 |
| 15 | 453900 |
| 16 | 926395 |
| 17 | 1882152 |
| 18 | 3812232 |
| 19 | 7699191 |
| 20 | 15518112 |
| 21 | 31220991 |
| 22 | 62733296 |
| 23 | 125911851 |
| 24 | 252516626 |
| 25 | 506082933 |
| 26 | 1013780968 |
| 27 | 2029989807 |
| 28 | 4063678159 |
| 29 | 8132877129 |
| 30 | 16274093175 |
[1,3,11,30,81,198,477,1089,2451,5358,11567,24537, 51577,107205,221378,453900,926395,1882152,3812232, 7699191,15518112,31220991,62733296,125911851, 252516626,506082933,1013780968,2029989807, 4063678159,8132877129,16274093175] |