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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 13 |
| 5 | 36 |
| 6 | 105 |
| 7 | 320 |
| 8 | 1011 |
| 9 | 3289 |
| 10 | 10957 |
| 11 | 37216 |
| 12 | 128435 |
| 13 | 449142 |
| 14 | 1588228 |
| 15 | 5669505 |
| 16 | 20403322 |
| 17 | 73945553 |
| 18 | 269647630 |
| 19 | 988642372 |
| 20 | 3642310793 |
| 21 | 13476857235 |
| 22 | 50059454347 |
| 23 | 186598634398 |
| 24 | 697777187275 |
| 25 | 2616919372356 |
| 26 | 9840647362248 |
[1,1,2,5,13,36,105,320,1011,3289,10957,37216, 128435,449142,1588228,5669505,20403322,73945553, 269647630,988642372,3642310793,13476857235, 50059454347,186598634398,697777187275, 2616919372356,9840647362248] |