(1+3+5·····+1995)-2乘(2+4+6+·····+1994)=

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(1+3+5·····+1995)-2乘(2+4+6+·····+1994)=

(1+3+5·····+1995)-2乘(2+4+6+·····+1994)=
(1+3+5·····+1995)-2乘(2+4+6+·····+1994)=

(1+3+5·····+1995)-2乘(2+4+6+·····+1994)=
=(1+3+5·····+1993+1995)-2×(1+1+1+3+1+5+·····1+1993)
=(1+3+5·····+1993)+1995-2×997-2×(1+3+5·····+1993)
=1-(1+3+5·····+1993)
=-994008
注释(1.997是1到1993取得奇数项,一共997项
2.1+3+5·····+1993可以用等差数列计算)
感觉应该对,