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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 10 |
| 4 | 22 |
| 5 | 42 |
| 6 | 84 |
| 7 | 154 |
| 8 | 298 |
| 9 | 568 |
| 10 | 1108 |
| 11 | 2142 |
| 12 | 4254 |
| 13 | 8362 |
| 14 | 16636 |
| 15 | 33076 |
| 16 | 66004 |
| 17 | 131556 |
| 18 | 262974 |
| 19 | 525136 |
| 20 | 1050016 |
| 21 | 2098756 |
| 22 | 4196962 |
| 23 | 8391288 |
| 24 | 16782312 |
| 25 | 33559612 |
| 26 | 67118176 |
| 27 | 134227594 |
| 28 | 268453714 |
| 29 | 536889198 |
| 30 | 1073777718 |
| 31 | 2147519572 |
[1,4,10,22,42,84,154,298,568,1108,2142,4254,8362, 16636,33076,66004,131556,262974,525136,1050016, 2098756,4196962,8391288,16782312,33559612, 67118176,134227594,268453714,536889198,1073777718, 2147519572] |