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| n | a(n) |
|---|---|
| 1 | 12 |
| 2 | 40 |
| 3 | 160 |
| 4 | 2176 |
| 5 | 10240 |
| 6 | 139264 |
| 7 | 655360 |
| 8 | 8912896 |
| 9 | 545259520 |
| 10 | 2684354560 |
| 11 | 139586437120 |
| 12 | 2336462209024 |
| 13 | 10995116277760 |
| 14 | 149533581377536 |
| 15 | 9147936743096320 |
| 16 | 585467951558164480 |
| 17 | 2882303761517117440 |
| 18 | 149879795598890106880 |
| 19 | 2508757194024499019776 |
| 20 | 11805916207174113034240 |
[12,40,160,2176,10240,139264,655360,8912896, 545259520,2684354560,139586437120,2336462209024, 10995116277760,149533581377536,9147936743096320, 585467951558164480,2882303761517117440, 149879795598890106880,2508757194024499019776, 11805916207174113034240] |