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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 5 |
| 3 | 10 |
| 4 | 20 |
| 5 | 36 |
| 6 | 74 |
| 7 | 134 |
| 8 | 272 |
| 9 | 526 |
| 10 | 1052 |
| 11 | 2058 |
| 12 | 4160 |
| 13 | 8204 |
| 14 | 16466 |
| 15 | 32824 |
| 16 | 65696 |
| 17 | 131088 |
| 18 | 262490 |
| 19 | 524306 |
| 20 | 1049168 |
| 21 | 2097316 |
| 22 | 4195358 |
| 23 | 8388630 |
| 24 | 16779632 |
| 25 | 33554516 |
| 26 | 67112996 |
| 27 | 134218282 |
| 28 | 268443848 |
| 29 | 536870940 |
| 30 | 1073759432 |
| 31 | 2147483678 |
[2,5,10,20,36,74,134,272,526,1052,2058,4160,8204, 16466,32824,65696,131088,262490,524306,1049168, 2097316,4195358,8388630,16779632,33554516, 67112996,134218282,268443848,536870940,1073759432, 2147483678] |