有整数x1，x2，x3，x4，x5，x6，x7。x1<x2<x3<x4<x5<x6<x7,x1+x2=x3,x2+x3=x4,x3+x4=x5,x4+x5=x6,x5+x6=x7 设x1，x2，x3，x4，x5，x6，x7为自然数，且x1＜...
\u8bbex1\uff0cx2\uff0cx3\uff0cx4\uff0cx5\uff0cx6\uff0cx7\u662f\u81ea\u7136\u6570\uff0c\u4e14x1\uff1cx2\uff1cx3\uff1cx4\uff1cx5\uff1cx6\uff1cx7\uff0cx1+x2=x3\uff0cx2+x3=x4\uff0cx3+x4=x5\uff0c\u2235x1+x2+x3+x4+x5+x6+x7=13x1+20x2=2010\uff0c\u5229\u7528\u6574\u9664\u6027\uff0cx1\u5fc5\u662f10\u7684\u5947\u6570\u500d\uff0c\u53c8x1\uff1cx2\uff0c\u53ef\u5f97x1\uff1d10x2\uff1d94\uff0cx1\uff1d30x2\uff1d81\uff0cx1\uff1d50x2\uff1d68\uff0c\uff08x1+x2+x3\uff09max=2\uff08x1+x2\uff09max=2\uff0850+68\uff09=236\uff0e\u6545\u7b54\u6848\u4e3a\uff1a236\uff0e
\u2235x1\uff1cx2\uff1cx3\uff1c\u2026x6\uff1cx7\uff0c\u53c8x1+x2+x3+x4+x5+x6+x7=159\uff0c\u2234x1+\uff08x1+1\uff09+\uff08x1+2\uff09\u2026+\uff08x1+6\uff09\u2264159\uff0c\u89e3\u5f97x1\u22641957\uff0c\u2234x1\u7684\u6700\u5927\u503c\u4e3a19\uff0c\u540c\u7406\u53ef\u5f97x2\u7684\u6700\u5927\u503c\u4e3a20\uff0cx3\u7684\u6700\u5927\u503c\u4e3a22\uff0c\u2234x1+x2+x3\u7684\u6700\u5927\u503c\u662f61\uff0e\u6545\u7b54\u6848\u4e3a61\uff0e
13x1+20x2=2010x1+x2+x3=2(x1+x2)=(2010+7x1)/10=201+0.7x1
因为x1 x2 x3都为自然数 固 设 x1=10k
∴x1<x2 即10k<(201-13k)/2 ∴k≤6 又因为k为奇数 k最大为5 此时x1+x2+x3取最大值为=236
k最小为1 最小值为208
20
绛旓細x1涓嶅彈闄愬埗涔堬紵0<=x1<=x2<=x3<x4<x5<=10 1) x1=x2=x3锛鏈塁(11锛3)=165(涓)2) x1=x2鈮爔3锛屾湁C(11锛4)=330(涓)3) x1鈮爔2=x3锛屾湁C(11锛4)=330(涓)4) x1鈮爔2鈮爔3锛屾湁C(11锛5)=462(涓)鍏辨湁 165+330+330+462=1287涓
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