BitOr[, , ... ] gives the bitwise OR of the integers .
Integer mathematical function (see Section A.3.10).
BitOr[, , ... ] yields the integer whose binary bit representation has ones at positions where the binary bit representations of any of the have ones. For negative integers BitOr assumes a two's complement representation. See The Mathematica Book on the web: Section 3.2.4. See also: BitAnd, BitXor, BitNot, Or, IntegerDigits.