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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 4 |
| 3 | 0 |
| 4 | 28 |
| 5 | 56 |
| 6 | 84 |
| 7 | 0 |
| 8 | 380 |
| 9 | 248 |
| 10 | 1364 |
| 11 | 0 |
| 12 | 5884 |
| 13 | 3448 |
| 14 | 22740 |
| 15 | 13696 |
| 16 | 91004 |
| 17 | 50936 |
| 18 | 363860 |
| 19 | 202752 |
| 20 | 1455868 |
| 21 | 814456 |
| 22 | 5822676 |
| 23 | 3257728 |
| 24 | 23290748 |
| 25 | 13027064 |
| 26 | 93162836 |
| 27 | 52107264 |
| 28 | 372651772 |
| 29 | 208432504 |
| 30 | 1490606292 |
| 31 | 833729920 |
| 32 | 5962425212 |
| 33 | 3334915832 |
| 34 | 23849700692 |
[1,0,4,0,28,56,84,0,380,248,1364,0,5884,3448, 22740,13696,91004,50936,363860,202752,1455868, 814456,5822676,3257728,23290748,13027064,93162836, 52107264,372651772,208432504,1490606292,833729920, 5962425212,3334915832,23849700692] |