Logic - Building formulas with conjunction and disjunction

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I am currently taking a logic class in uni and I have some problems with building formulas using $\bigwedge$ and $\bigvee$.

At example he used

$\phi_n = \bigwedge_{i<j<n} \bigvee_{k<n}(Y_{il} \wedge Y\wedge...\wedge Y_{l<j})$

to build a non directed connected graph. I don't really understand how you cann express something with disjunction and conjunction.

Any help helping me to understand it would be very appreciated since the class is really fun and I would like to be good in it.

Edit:

I know what $\bigwedge, \bigvee,Y$ etc. mean.

I do understand the general concept but I can not wrap my mind around how I use $\bigwedge$ and $\bigvee$ in combination with literals to create formula to express something like at example a graph.

Edit 2:

Sorry, I have been pretty busy today and haven't managed tc check until.

The meaning of $Y_{ij}$ is $X_{ix} \,for\, x<j, X_{ij} \,for\, i<j \, and \, 0 \, for\ x=j$

Furthermore

$G=(V,E$ ) is a non directed graph with V={0, . . . , n − 1) with the set of variables $\tau_n:= (X_{ij}: 0 ≤ i < j < n$) so $\, I_G(X_{ij}) = 1$ if {i,j} ∈ E