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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 9 |
| 4 | 21 |
| 5 | 48 |
| 6 | 106 |
| 7 | 227 |
| 8 | 475 |
| 9 | 978 |
| 10 | 1992 |
| 11 | 4029 |
| 12 | 8113 |
| 13 | 16292 |
| 14 | 32662 |
| 15 | 65415 |
| 16 | 130935 |
| 17 | 261990 |
| 18 | 524116 |
| 19 | 1048385 |
| 20 | 2096941 |
| 21 | 4194072 |
| 22 | 8388354 |
| 23 | 16776939 |
| 24 | 33554131 |
| 25 | 67108538 |
| 26 | 134217376 |
| 27 | 268435077 |
| 28 | 536870505 |
| 29 | 1073741388 |
| 30 | 2147483182 |
| 31 | 4294966799 |
| 32 | 8589934063 |
[1,2,4,9,21,48,106,227,475,978,1992,4029,8113, 16292,32662,65415,130935,261990,524116,1048385, 2096941,4194072,8388354,16776939,33554131, 67108538,134217376,268435077,536870505,1073741388, 2147483182,4294966799,8589934063] |