The problem is from Problem 45436, https://www.mathworks.com/matlabcentral/cody/problems/45436-successive-zeros
Suppose n is the number of digits a number contains.
12032 - is a valid n=5 digit number. But 10023 - is defined as invalid -- because it contains two successive zeros.
Calculate the number of n-digit numbers that do not contain successive d-number of zeros.
The difference is adding more big integers to the test. Your algorithm needs to be much faster!