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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 24 |
| 4 | 98 |
| 5 | 381 |
| 6 | 1626 |
| 7 | 6793 |
| 8 | 29484 |
| 9 | 128021 |
| 10 | 564403 |
| 11 | 2500084 |
| 12 | 11170691 |
| 13 | 50116462 |
| 14 | 226143658 |
| 15 | 1024155781 |
| 16 | 4656130957 |
| 17 | 21235409051 |
| 18 | 97128731541 |
| 19 | 445394455074 |
| 20 | 2047219553857 |
| 21 | 9429370132204 |
| 22 | 43515500709007 |
| 23 | 201169480526362 |
| 24 | 931494523678825 |
| 25 | 4319608455445313 |
| 26 | 20058776859173756 |
| 27 | 93264842819390272 |
[1,2,7,24,98,381,1626,6793,29484,128021,564403, 2500084,11170691,50116462,226143658,1024155781, 4656130957,21235409051,97128731541,445394455074, 2047219553857,9429370132204,43515500709007, 201169480526362,931494523678825,4319608455445313, 20058776859173756,93264842819390272] |