Do you understand the rationale behind these representations?

For example, decimal numbers use ten as a

*base.* This means that each digit represents a quantity multiplied by ten raised to some power. Specifically, the right digit is multiplied by 10^0, the digit to the left of that is multiplied by 10^1, the digit to the left of that is multiplied by 10^2, and so on.

So in base ten, 987 means (9 * 10^2) + (8 * 10^1) + (7 * 10^0).

In binary, the base is two, so 101 means (1 * 2^2) + (0 * 2^1) + (1 * 2^0).

In octal, the base is eight, so 765 means (7 * 8^2) + (6 * 8^1) + (5 * 8^0).

In hexadecimal, the base is 16 (with letters a-f used to represent 10-15), so c9a means (12 * 16^2) + (9 * 16^1) + (10 * 16^0).

With this understanding, do you see the

patterns below?