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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 5 |
| 4 | 10 |
| 5 | 20 |
| 6 | 40 |
| 7 | 80 |
| 8 | 160 |
| 9 | 320 |
| 10 | 640 |
| 11 | 1280 |
| 12 | 2560 |
| 13 | 5120 |
| 14 | 10240 |
| 15 | 20480 |
| 16 | 40960 |
| 17 | 81920 |
| 18 | 163840 |
| 19 | 327680 |
| 20 | 655360 |
| 21 | 1310720 |
| 22 | 2621440 |
| 23 | 5242880 |
| 24 | 10485760 |
| 25 | 20971520 |
| 26 | 41943040 |
| 27 | 83886080 |
| 28 | 167772160 |
| 29 | 335544320 |
| 30 | 671088640 |
| 31 | 1342177280 |
| 32 | 2684354560 |
| 33 | 5368709120 |
| 34 | 10737418240 |
[2,3,5,10,20,40,80,160,320,640,1280,2560,5120, 10240,20480,40960,81920,163840,327680,655360, 1310720,2621440,5242880,10485760,20971520, 41943040,83886080,167772160,335544320,671088640, 1342177280,2684354560,5368709120,10737418240] |