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| n | a(n) |
|---|---|
| 0 | 4 |
| 1 | 5 |
| 2 | 5 |
| 3 | 5 |
| 4 | 9 |
| 5 | 25 |
| 6 | 65 |
| 7 | 145 |
| 8 | 289 |
| 9 | 545 |
| 10 | 1025 |
| 11 | 1985 |
| 12 | 3969 |
| 13 | 8065 |
| 14 | 16385 |
| 15 | 33025 |
| 16 | 66049 |
| 17 | 131585 |
| 18 | 262145 |
| 19 | 523265 |
| 20 | 1046529 |
| 21 | 2095105 |
| 22 | 4194305 |
| 23 | 8392705 |
| 24 | 16785409 |
| 25 | 33562625 |
| 26 | 67108865 |
| 27 | 134201345 |
| 28 | 268402689 |
| 29 | 536838145 |
| 30 | 1073741825 |
| 31 | 2147549185 |
| 32 | 4295098369 |
| 33 | 8590065665 |
[4,5,5,5,9,25,65,145,289,545,1025,1985,3969,8065, 16385,33025,66049,131585,262145,523265,1046529, 2095105,4194305,8392705,16785409,33562625, 67108865,134201345,268402689,536838145,1073741825, 2147549185,4295098369,8590065665] |