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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 32 |
| 5 | 122 |
| 6 | 490 |
| 7 | 2044 |
| 8 | 8769 |
| 9 | 38455 |
| 10 | 171606 |
| 11 | 776763 |
| 12 | 3557681 |
| 13 | 16457402 |
| 14 | 76778667 |
| 15 | 360830164 |
| 16 | 1706641162 |
| 17 | 8117569255 |
| 18 | 38804142203 |
| 19 | 186323145806 |
| 20 | 898247214881 |
| 21 | 4346078073871 |
| 22 | 21097315227638 |
| 23 | 102721050351404 |
| 24 | 501515949459113 |
| 25 | 2454747530072567 |
| 26 | 12043165949629976 |
[1,1,3,9,32,122,490,2044,8769,38455,171606,776763, 3557681,16457402,76778667,360830164,1706641162, 8117569255,38804142203,186323145806,898247214881, 4346078073871,21097315227638,102721050351404, 501515949459113,2454747530072567, 12043165949629976] |