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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 14 |
| 3 | 61 |
| 4 | 252 |
| 5 | 1019 |
| 6 | 4090 |
| 7 | 16377 |
| 8 | 65528 |
| 9 | 262135 |
| 10 | 1048566 |
| 11 | 4194293 |
| 12 | 16777204 |
| 13 | 67108851 |
| 14 | 268435442 |
| 15 | 1073741809 |
| 16 | 4294967280 |
| 17 | 17179869167 |
| 18 | 68719476718 |
| 19 | 274877906925 |
| 20 | 1099511627756 |
| 21 | 4398046511083 |
| 22 | 17592186044394 |
| 23 | 70368744177641 |
| 24 | 281474976710632 |
| 25 | 1125899906842599 |
[1,3,14,61,252,1019,4090,16377,65528,262135, 1048566,4194293,16777204,67108851,268435442, 1073741809,4294967280,17179869167,68719476718, 274877906925,1099511627756,4398046511083, 17592186044394,70368744177641,281474976710632, 1125899906842599] |