operator: $\sum$ , operator: $B$ , minus operator: $-$

operator: $\sum$ , operator: $B$ , minus operator: $-$

operator: $\sum$ , operator: $B$ , minus operator: $-$

operator: $\sum \sum \sum$ , operator: $BBB$ , minus operator: $---$

operator: $|\int \{[\text{<div style="display: inline-block; height: 50px; width: 50px; vertical-align: -33\%; border: 1px solid black; margin-left: 2px; margin-right: 2px;"> <mo>]</mo> <mo>}</mo> <p></p> <p id="t6"> <math xmlns="http://www.w3.org/1998/Math/MathML" style="font-size: 3em"> <mo>|</mo> <mfrac> <mi>f</mi> <mi>g</mi> </mfrac> <mo>|</mo> </math> </p> </div>}$