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| n | a(n) |
|---|---|
| 4 | 0 |
| 5 | 0 |
| 6 | 2 |
| 7 | 3 |
| 8 | 12 |
| 9 | 23 |
| 10 | 61 |
| 11 | 132 |
| 12 | 294 |
| 13 | 639 |
| 14 | 1377 |
| 15 | 2922 |
| 16 | 6178 |
| 17 | 12953 |
| 18 | 27021 |
| 19 | 56106 |
| 20 | 116030 |
| 21 | 239090 |
| 22 | 491202 |
| 23 | 1006361 |
| 24 | 2056755 |
| 25 | 4194230 |
| 26 | 8536023 |
| 27 | 17340787 |
| 28 | 35168957 |
| 29 | 71217347 |
| 30 | 144012394 |
| 31 | 290835635 |
| 32 | 586637532 |
| 33 | 1181960546 |
| 34 | 2378920014 |
| 35 | 4783326807 |
| 36 | 9609050910 |
| 37 | 19286596636 |
[0,0,2,3,12,23,61,132,294,639,1377,2922,6178, 12953,27021,56106,116030,239090,491202,1006361, 2056755,4194230,8536023,17340787,35168957, 71217347,144012394,290835635,586637532,1181960546, 2378920014,4783326807,9609050910,19286596636] |