this might help

#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>

int main() 
{
    int i,j,s,x,n;
    scanf("%d",&n);
    for(i=1; i<=n; i++)
    {
        s=n-1;
        x=i;
        for(j=1;j<=i;j++)
        {
            printf("%d ",x);
            x+=s;
            s--;
        }
        printf("\n");
    }
    return 0;
}