Sorry, but it's not so simple. <s>& halves the number of 1's only if both expression are identical, same thing for |<s>.

In fact, if I'm right, your expression for 21 gives an average of 23 ones and the expression for 27 gives an average of 29.

Update: on second sight, your solution for 27 is equivalent to that given by BrowserUk for 29

Update: & doesn't half the number of 1's. The result is the product divided by 32, so it halves the number of 1's of an expression if and only if the other is R

Rule One: "Do not act incautiously when confronting a little bald wrinkly smiling man."

In reply to Re^2: Boolean math: Fill in the blanks. by psini
in thread Boolean math: Fill in the blanks. by BrowserUk

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