=(x^(n+1)-x)/(x-1) It's high school Mathematics.

jwu (g2w)
Y = x+x^2+x^3+x^4.....x^n ----------------(1)
xY = x^2+x^3+x^4.....x^n+x^(n+1)--------(2)
(2)-(1) you get:
(x-1)Y = x^(n+1)-x
so: Y =(x^(n+1)-x)/(x-1)
(#352638@0)
2002-1-30 -05:00
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