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| n | a(n) |
|---|---|
| 3 | 1 |
| 4 | 4 |
| 5 | 6 |
| 6 | 18 |
| 7 | 36 |
| 8 | 80 |
| 9 | 172 |
| 10 | 360 |
| 11 | 760 |
| 12 | 1576 |
| 13 | 3264 |
| 14 | 6720 |
| 15 | 13776 |
| 16 | 28160 |
| 17 | 57376 |
| 18 | 116640 |
| 19 | 236608 |
| 20 | 479104 |
| 21 | 968640 |
| 22 | 1955712 |
| 23 | 3944064 |
| 24 | 7945856 |
| 25 | 15993856 |
| 26 | 32168448 |
| 27 | 64656640 |
| 28 | 129879040 |
| 29 | 260759040 |
| 30 | 523289088 |
| 31 | 1049711616 |
| 32 | 2104967168 |
| 33 | 4219743232 |
| 34 | 8456841216 |
| 35 | 16944388096 |
[1,4,6,18,36,80,172,360,760,1576,3264,6720,13776, 28160,57376,116640,236608,479104,968640,1955712, 3944064,7945856,15993856,32168448,64656640, 129879040,260759040,523289088,1049711616, 2104967168,4219743232,8456841216,16944388096] |