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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 10 |
| 4 | 36 |
| 5 | 94 |
| 6 | 284 |
| 7 | 692 |
| 8 | 1828 |
| 9 | 4124 |
| 10 | 9828 |
| 11 | 20798 |
| 12 | 45564 |
| 13 | 91018 |
| 14 | 186788 |
| 15 | 355906 |
| 16 | 692004 |
| 17 | 1264678 |
| 18 | 2347716 |
| 19 | 4138358 |
| 20 | 7389572 |
| 21 | 12625938 |
| 22 | 21804900 |
| 23 | 36243644 |
| 24 | 60777212 |
| 25 | 98547380 |
| 26 | 160987868 |
| 27 | 255297602 |
| 28 | 407492292 |
| 29 | 633469718 |
| 30 | 990388828 |
| 31 | 1512185428 |
| 32 | 2320518948 |
[1,1,4,10,36,94,284,692,1828,4124,9828,20798, 45564,91018,186788,355906,692004,1264678,2347716, 4138358,7389572,12625938,21804900,36243644, 60777212,98547380,160987868,255297602,407492292, 633469718,990388828,1512185428,2320518948] |