x 3=x1+x2
x4=x 2+x 3=x1+2x2
x5=x 3+x4=2x1+3x2
x6=x4+x5=3x1+5x2
x7=x5+x6=5x1+8x2
x1+x2+x3+x4+x5+x6+x7=13x1+20x2=2010
x1x2是自然数2010-13x1要能被20整除,且x1<x2
x1=10,30,50
x2=94,81,68
x1+x2最大值50+68=118
x1+x2+x3最大值=118+118=236
x 3=x1+x2
x4=x 2+x 3=x1+2x2
x5=x 3+x4=2x1+3x2
x6=x4+x5=3x1+5x2
x7=x5+x6=5x1+8x2
x1+x2+x3+x4+x5+x6+x7=13x1+20x2=2010
x1x2是自然数2010-13x1要能被20整除,且x1<x2
x1=10,30,50
x2=94,81,68
x1+x2最大值50+68=118
x1+x2+x3最大值=118+118=236