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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 2 |
| 3 | 6 |
| 4 | 10 |
| 5 | 26 |
| 6 | 50 |
| 7 | 114 |
| 8 | 226 |
| 9 | 482 |
| 10 | 962 |
| 11 | 1986 |
| 12 | 3970 |
| 13 | 8066 |
| 14 | 16130 |
| 15 | 32514 |
| 16 | 65026 |
| 17 | 130562 |
| 18 | 261122 |
| 19 | 523266 |
| 20 | 1046530 |
| 21 | 2095106 |
| 22 | 4190210 |
| 23 | 8384514 |
| 24 | 16769026 |
| 25 | 33546242 |
| 26 | 67092482 |
| 27 | 134201346 |
| 28 | 268402690 |
| 29 | 536838146 |
| 30 | 1073676290 |
| 31 | 2147418114 |
| 32 | 4294836226 |
| 33 | 8589803522 |
[2,2,6,10,26,50,114,226,482,962,1986,3970,8066, 16130,32514,65026,130562,261122,523266,1046530, 2095106,4190210,8384514,16769026,33546242, 67092482,134201346,268402690,536838146,1073676290, 2147418114,4294836226,8589803522] |