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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 4 |
| 4 | 7 |
| 5 | 18 |
| 6 | 29 |
| 7 | 70 |
| 8 | 126 |
| 9 | 266 |
| 10 | 507 |
| 11 | 1054 |
| 12 | 2037 |
| 13 | 4158 |
| 14 | 8183 |
| 15 | 16488 |
| 16 | 32760 |
| 17 | 65790 |
| 18 | 131026 |
| 19 | 262654 |
| 20 | 524265 |
| 21 | 1049524 |
| 22 | 2097119 |
| 23 | 4196350 |
| 24 | 8388450 |
| 25 | 16781292 |
| 26 | 33554367 |
| 27 | 67116784 |
| 28 | 134217657 |
| 29 | 268451838 |
[0,1,4,7,18,29,70,126,266,507,1054,2037,4158,8183, 16488,32760,65790,131026,262654,524265,1049524, 2097119,4196350,8388450,16781292,33554367, 67116784,134217657,268451838] |