for i := 0; i < len(a); i += 5 { // ERROR "Induction variable: limits \[0,20\], increment 5$"
		useString(a[i:]) // ERROR "(\([0-9]+\) )?Proved IsSliceInBounds$"
		useString(a[:i+3]) // ERROR "(\([0-9]+\) )?Proved IsSliceInBounds$"
		useString(a[:i+5]) // ERROR "(\([0-9]+\) )?Proved IsSliceInBounds$"
		useString(a[:i+6])
	}
}

func g3b(a string) {