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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 4 |
| 4 | 14 |
| 5 | 14 |
| 6 | 40 |
| 7 | 40 |
| 8 | 106 |
| 9 | 106 |
| 10 | 254 |
| 11 | 254 |
| 12 | 582 |
| 13 | 582 |
| 14 | 1256 |
| 15 | 1256 |
| 16 | 2620 |
| 17 | 2620 |
| 18 | 5256 |
| 19 | 5256 |
| 20 | 10266 |
| 21 | 10266 |
| 22 | 19482 |
| 23 | 19482 |
| 24 | 36204 |
| 25 | 36204 |
| 26 | 65792 |
| 27 | 65792 |
| 28 | 117496 |
| 29 | 117496 |
| 30 | 206120 |
| 31 | 206120 |
| 32 | 356320 |
| 33 | 356320 |
| 34 | 606912 |
| 35 | 606912 |
| 36 | 1020848 |
| 37 | 1020848 |
| 38 | 1695676 |
| 39 | 1695676 |
| 40 | 2786010 |
[1,1,4,4,14,14,40,40,106,106,254,254,582,582,1256, 1256,2620,2620,5256,5256,10266,10266,19482,19482, 36204,36204,65792,65792,117496,117496,206120, 206120,356320,356320,606912,606912,1020848, 1020848,1695676,1695676,2786010] |