证明题???
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#include<stdio.h>
int main()
{
int n,sum=0,i;
printf("请输入n的值:");
scanf("%d",&n);
for(i=1;i<=n;i++)
{
sum=sum+i*(i+1);
}
for(i=1;i<n;i++)
printf("%d*%d+",i,i+1);
printf("%d*%d=%d\n",n,n+1,sum);
printf("%d*(%d+1)*(%d+2)/3=%d\n",n,n,n,n*(n+1)*(n+2)/3);
printf("所以");
for(i=1;i<n;i++)
printf("%d*%d+",i,i+1);
printf("%d*%d = ",n,n+1);
printf("%d*(%d+1)*(%d+2)/3\n",n,n,n);
}