3 & # 179; - 4 * 3 & # 178; + 10 * 3 = the fourth power of 3 - 4 * 3 & # 179; + 10 * 3 & # 178; = and find out the rule

3 & # 179; - 4 * 3 & # 178; + 10 * 3 = the fourth power of 3 - 4 * 3 & # 179; + 10 * 3 & # 178; = and find out the rule

3³-4*3²+10*3=21=7*3
The fourth power of 3 - 4 * 3 & # 179; + 10 * 3 & # 178; = 63 = 7 * 3 & # 178;
The fifth power of 3 - 4 * 3 ^ 4 + 10 * 3 & # 179; = 189 = 7 * 3 & # 179;
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3^(n+2)-4*3^(n+1)+10*3^n=7*3^n