How to omit indent of paragraph after math block?

Edit: Now irrelevant since the question was updated.

Hello @Vaclav_Bocan , this seems similar to How can I change the spacing between lines of a math.equation in "block" mode? - #4 by SillyFreak

I would try something like

#show math.equation.where(block: true): set par(first-line-indent: 0pt)

Although from your example, it doesn’t matter as the block equations are centered by default.