Complete the sequence

Find the next number that fits the pattern:

4Explanation:s(n) = multiply together the digits in the previous number and substract the first digit9536 = (9 * 5) - 9 = 45 - 915 = (3 * 6) - 3 = 18 - 34 = (1 * 5) - 1 = 5 - 1 Show correct answer