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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 14 |
| 4 | 43 |
| 5 | 136 |
| 6 | 443 |
| 7 | 1478 |
| 8 | 5027 |
| 9 | 17368 |
| 10 | 60788 |
| 11 | 215084 |
| 12 | 768094 |
| 13 | 2764880 |
| 14 | 10021721 |
| 15 | 36546310 |
| 16 | 133990755 |
| 17 | 493606680 |
| 18 | 1826192640 |
| 19 | 6782469540 |
| 20 | 25278252810 |
| 21 | 94512157680 |
| 22 | 354397639830 |
| 23 | 1332454176924 |
| 24 | 5022040887822 |
[1,2,5,14,43,136,443,1478,5027,17368,60788,215084, 768094,2764880,10021721,36546310,133990755, 493606680,1826192640,6782469540,25278252810, 94512157680,354397639830,1332454176924, 5022040887822] |