#include <stdio.h>

void sequence(int n)
{
    if (n > 0) {
    	printf("%d ", n); sequence(n-5); printf(" %d", n);
    } else {
        printf("%d", n);
    }
}

int main() {
    sequence(16); printf("\n");
    sequence(10); printf("\n");
    sequence(9); printf("\n");
    return 0;
}