B1 = -1
问题描述:
B1 = -1
B2 = -2
B3 = -6
B4 = -22
B5 = -86 求Bn
答
b(n+1)=bn-4^(n-1)
bn=-1-[1+4+4^2+...+4^(n-2)]
=-1-[4^(n-1)-1]/3