Show inline math as if it were display math
I have a formula in an equation environmente i.e., in a display style modality.
Moreover, since I have to enumerate an operator, I want to put a subscript on it:
\[ \sum_1 \]. This subscript does not represent the lower bound of the summation symbol, but its number and then even in display style mode it has to be put in normal subscript position.
How can I achieve it?