Given,
A=1,2,3,….7
And f:A→P(A) and a∈A
Also a∈f(a), that means ‘a’ will be the element of subset as f:A→P(A),
Now, total options for 1 will be 26. (Because 26 subsets contains elements1)
Similarly, for every other element we get, total 26×26×26×26×26×26×26=242 subsets.
Now, comparing with mn we get, m=2&n=42
Hence, m+n=2+42=44