Odd-carbon formula

A formula is called an even—carbon formula when n and s (which necessarily have the same parity) are even integers, while is an odd-carbon formula when n and s are odd. In Table 3 (as well as in Table 3.5) it is found that the even-carbon— and odd-carbon formulas occur in alternating columns. They are characterized by n = 0, 2, 4, 6,. and n = 1, 3, 5, 7, respectively. 

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