#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;
}
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