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| n | a(n) |
|---|---|
| 1 | 13 |
| 2 | 58 |
| 3 | 244 |
| 4 | 1000 |
| 5 | 4048 |
| 6 | 16288 |
| 7 | 65344 |
| 8 | 261760 |
| 9 | 1047808 |
| 10 | 4192768 |
| 11 | 16774144 |
| 12 | 67102720 |
| 13 | 268423168 |
| 14 | 1073717248 |
| 15 | 4294918144 |
| 16 | 17179770880 |
| 17 | 68719280128 |
| 18 | 274877513728 |
| 19 | 1099510841344 |
| 20 | 4398044938240 |
| 21 | 17592182898688 |
| 22 | 70368737886208 |
[13,58,244,1000,4048,16288,65344,261760,1047808, 4192768,16774144,67102720,268423168,1073717248, 4294918144,17179770880,68719280128,274877513728, 1099510841344,4398044938240,17592182898688, 70368737886208] |