These are some formula`s I came across doing clock branching, but may serve many needs outside clocking.

Unlike a prime number, which is divisible by one number only. You can create numbers that are divisible by any integer up to a given point. The simplest form of making such numbers is by multiplication into a series that is constructed by multiplying integers like so.

12 = 3*4 (divisible by 2, 3 and 4)

30 = 3*4*5 (divisible by 2, 3, 4 and 5)

210 = 3*4*5*7 (divisible by 2, 3, 4, 5, 6 and 7)

1890 = 3*4*5*7*9 (divisible by 2, 3, 4, 5, 6, 7 and 9) and not yet by 8, but you can multiply it by 4 and be done.

Since even numbers are much more friendly than the odd ones for division, you can compress these series to fit your needs at any given point. By multiplying it by 2 or 4.

This works with the Fibonacci series as well.

To express a series rather than building it from the start.

2*3*5*8*13*21*34*55 = 122522400 which is compressed and divisible by any number up to 18, also it can be multiplied as a result by any fraction like 0.1 up to a given point and still produce an integer outcome.