Table 1. Constraints on D and allele frequencies for locus A and locus B to ensure admissibility of haplotype allele frequencies in population i.

	Constraints
Sign of D	On D	On b1∣D	On a1|D, b1
Positive	$D\le \frac{1}{4}$	$\left|b_1-\frac{1}{2}\right|\le \sqrt{1-4D}$	$\frac{D}{1-b_1}\le a_1\le 1-\frac{D}{b_1}$
Negative	$D\ge -\frac{1}{4}$	$\left|b_1-\frac{1}{2}\right|\le \sqrt{1+4D}$	$-\frac{D}{b_1}\le a_1\ge 1+\frac{D}{1-b_1}$

The exponent (i) is omitted for convenience.