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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 51 |
| 5 | 201 |
| 6 | 819 |
| 7 | 3389 |
| 8 | 14131 |
| 9 | 59341 |
| 10 | 250703 |
| 11 | 1064207 |
| 12 | 4535091 |
| 13 | 19390229 |
| 14 | 83139955 |
| 15 | 357354213 |
| 16 | 1539272499 |
| 17 | 6642769925 |
| 18 | 28714955571 |
| 19 | 124312591469 |
| 20 | 538895612751 |
| 21 | 2338948779320 |
| 22 | 10162837993377 |
| 23 | 44202371860240 |
| 24 | 192431323820851 |
| 25 | 838442649862701 |
| 26 | 3656031108325651 |
[1,1,3,13,51,201,819,3389,14131,59341,250703, 1064207,4535091,19390229,83139955,357354213, 1539272499,6642769925,28714955571,124312591469, 538895612751,2338948779320,10162837993377, 44202371860240,192431323820851,838442649862701, 3656031108325651] |