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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 4 |
| 3 | 6 |
| 4 | 12 |
| 5 | 24 |
| 6 | 42 |
| 7 | 84 |
| 8 | 168 |
| 9 | 312 |
| 10 | 624 |
| 11 | 1140 |
| 12 | 2280 |
| 13 | 4560 |
| 14 | 8700 |
| 15 | 17400 |
| 16 | 32820 |
| 17 | 65640 |
| 18 | 131280 |
| 19 | 254460 |
| 20 | 508920 |
| 21 | 978120 |
| 22 | 1956240 |
| 23 | 3743880 |
| 24 | 7487760 |
| 25 | 14975520 |
| 26 | 29270220 |
| 27 | 58540440 |
| 28 | 113716680 |
| 29 | 227433360 |
| 30 | 440389320 |
| 31 | 880778640 |
| 32 | 1761557280 |
| 33 | 3463686240 |
[2,4,6,12,24,42,84,168,312,624,1140,2280,4560, 8700,17400,32820,65640,131280,254460,508920, 978120,1956240,3743880,7487760,14975520,29270220, 58540440,113716680,227433360,440389320,880778640, 1761557280,3463686240] |