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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 8 |
| 4 | 32 |
| 5 | 142 |
| 6 | 668 |
| 7 | 3264 |
| 8 | 16444 |
| 9 | 84756 |
| 10 | 444793 |
| 11 | 2368800 |
| 12 | 12769602 |
| 13 | 69545358 |
| 14 | 382075868 |
| 15 | 2114965120 |
| 16 | 11784471548 |
| 17 | 66043042088 |
| 18 | 372022512608 |
| 19 | 2105220502772 |
| 20 | 11962163400706 |
| 21 | 68223286792200 |
| 22 | 390406746862530 |
| 23 | 2240962117491470 |
| 24 | 12899456450932840 |
[1,1,2,8,32,142,668,3264,16444,84756,444793, 2368800,12769602,69545358,382075868,2114965120, 11784471548,66043042088,372022512608, 2105220502772,11962163400706,68223286792200, 390406746862530,2240962117491470, 12899456450932840] |