Sum as x goes from a to b of f(x)
<math xmlns="http://www.w3.org/1998/Math/MathML">
<apply>
<sum/>
<bvar>
<ci>x</ci>
</bvar>
<lowlimit>
<ci>a</ci>
</lowlimit>
<uplimit>
<ci>b</ci>
</uplimit>
<apply>
<fn>
<ci>f</ci>
</fn>
<ci>x</ci>
</apply>
</apply>
</math>
Author: Design Science, Inc. (E. Cannon, E. Tabacman, R.Miner)