Some heuristics for solving problems are:
We can see that there is a number sequences. The number of that particular layer was added by the previous layer to het the amount of zeroes. Example:
4 layers= the number of zeroes for 3 layers is 6 and add 4 to 6 you will get 10 and the amount of zeroes is indeed 10 for 4 layers. We have to find a formula to get the answer and the formula is to take the number of that particular layer and add one to it. After adding one, take the number of that layer and mulitply it by the number which was added by one. After getting the answer, divide it by 2 and you will get the number of zeroes.
Problem
solving requires the skill of spotting pattern and even though some patterns
may not make sense to you sometimes, as long as you have the formula, you
can find the answer. Always remeber to simplify a problem first before
finding a pattern.