Syntax: @NAND(argumentlist)
argumentlist = any combination or numbers, cell, or ranges
@NAND returns 0 if all arguments are 1; 1 if any argument is 0; otherwise -1 (unknown).
Examples:
A1 = 1, B1 = 1, C1 = 0, D1 = 0, E1 = 1 and A2 = 24
@NAND(A1, B1) = 0
@NAND(A1..E1) = 1
@NAND(A1..A2) = -1