#include <stdio.h>
int main()
{
int n = 0;
int i = 0;
scanf("%d",&n);
int m = n;
printf("%d", 1 + n * (n - 1));
for (i = 1; m>1;m-- ,i++)
{
printf("+%d", 1 + n * (n - 1)+2*i);
}
printf("\n");
return 0;
}

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