ger multiples of 60. The last equation means that <span class="nowrap">P<sub>s</sub>N - r<sub>2</sub></span> is an integer multiples of <span class="nowrap">P<sub>L</sub></span>. Note that <span class="nowrap">R<sub>0</sub></span> is an integer, but <span class="nowrap">r<sub>1</sub></span> and <span class="nowrap">r<sub>2</sub></span> are not.</p><p>To convert the equations in (1) into equations involving only integers, write the synodic month <span class="nowrap">P<sub>L</sub>=U/A</span>, where both U and