its a binary AND operation.
5 = 00000101
17 = 00010001
the only column in BOTH values binary representation above is the first column, representing 2^0, so the value is 1.
16 = 00010000
17 = 00010001
when AND-ing 16, and 16, the only shared column si the 2^4 column, which is 16.
Lowell
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