Tricky pattern in c language

#include<stdio.h>

int main( ){

	int wh=5; 

	int wl=4;

	int i,j,k;

	int is=1; //inner space 

	int os =2; //outer space

	for(i=0; i<=wh; i++){

		for(j=1; j<=wl; j++){

			for(k=0; k<=os; k++){

				printf(" ");

			}

			printf("%d",j);

			for(k=1; k<=is; k++){

				printf(" ");

			}

			printf("%d",j);

			for(k=1; k<=os; k++){

				printf(" ");

			}

			printf(" ");

		}

		os=(i+1!=wh);

		is=(i+1!=wh)?3:5;

		printf("\n");

	}

	return 0;

}

Output: