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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 8 |
| 2 | 46 |
| 3 | 230 |
| 4 | 1066 |
| 5 | 4718 |
| 6 | 20266 |
| 7 | 85310 |
| 8 | 354106 |
| 9 | 1455278 |
| 10 | 5938186 |
| 11 | 24104990 |
| 12 | 97478746 |
| 13 | 393095438 |
| 14 | 1581931306 |
| 15 | 6356390270 |
| 16 | 25511588986 |
| 17 | 102304505198 |
| 18 | 409992599626 |
| 19 | 1642294397150 |
| 20 | 6576150108826 |
| 21 | 26325519044558 |
| 22 | 105364834103146 |
| 23 | 421647614381630 |
| 24 | 1687155299822266 |
[1,8,46,230,1066,4718,20266,85310,354106,1455278, 5938186,24104990,97478746,393095438,1581931306, 6356390270,25511588986,102304505198,409992599626, 1642294397150,6576150108826,26325519044558, 105364834103146,421647614381630,1687155299822266] |