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| n | a(n) |
|---|---|
| 1 | 40 |
| 2 | 96 |
| 3 | 214 |
| 4 | 446 |
| 5 | 920 |
| 6 | 1852 |
| 7 | 3716 |
| 8 | 7414 |
| 9 | 14772 |
| 10 | 29486 |
| 11 | 58836 |
| 12 | 117908 |
| 13 | 236354 |
| 14 | 475986 |
| 15 | 959170 |
| 16 | 1940794 |
| 17 | 3930106 |
| 18 | 7985174 |
| 19 | 16237818 |
| 20 | 33106698 |
| 21 | 67555856 |
| 22 | 138133826 |
| 23 | 282669656 |
| 24 | 579365960 |
| 25 | 1188357854 |
| 26 | 2440574368 |
| 27 | 5015738686 |
| 28 | 10318671714 |
[40,96,214,446,920,1852,3716,7414,14772,29486, 58836,117908,236354,475986,959170,1940794,3930106, 7985174,16237818,33106698,67555856,138133826, 282669656,579365960,1188357854,2440574368, 5015738686,10318671714] |