How many reflexive but not antisymmetric relations are there?

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Question: How many reflexive but not antisymmetric relations are there on a set A containing n elements?

So N(reflexive but not antisymmetric) = N(reflexive functions) - N(reflexive and antisymmetric). The number of reflexive relations over A $2^{n^2-n}$, but how would I get the number of reflexive and antisymmetric relations over A? Thanks.