I have actually 2 ideas around it: It implies the number of times the expression in satisfied or it transforms for \$1\$ or \$0\$ relying on the outcome eincredibly time the \$i\$ value changes.

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This kind of square-bracket is used in various context. One application is indeed for some authorize functions.

In your example it is offered identical to the so called Iverboy Bracket. In this case the particular use of square brackets was supported by Donald Knuth to prevent ambiguity in parenthesized logical expressions.

But beyond your example beware, there are various other applications such as \$<>\$ might mean round dvery own to the best integer much less than or equal to \$z\$ etc.

In this instance, the symbol is an Iverboy bracket, characterized by\$\$ = egincases 0 & extif phi extis false \ 1 & extif phi extis true endcases\$\$wbelow \$phi\$ is some formula.

This is rather off-topic, however could aid.

Coxeter and Johnboy, usage square brackets to note of a symmetry, eg <3,3> is the symmeattempt of 3,3, but usage double-square brackets to include a second extension ie <<3,3>> is the tetrahedral symmeattempt, along with swapping a figure and also its dual. For this team, main inversion functions, but for <<3,4,3>> in 4D, one demands one of Conway/Thurston"s "wanders" to move the two.

It could very well just be a parenthetical statement (as in the English grammatical construct); e.g. that the equation to the left is true just if the problem on the best holds, or as an explacountry as to why the equation is true, or perhaps something else. This interpretation is urged by the appearance of what shows up to be a period at the finish of the equation on the left.

As others have actually shelp, actually showing the context would help clear points up.

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