Let Tr be the rth term of an A.P. for r=1,2,3,... If for some positive integers m, n we have Tm=1n and Tn=1m, then Tmn equals
Let Tr be the rth term of an A.P, for r=1, 2, 3,-------. If for some positive integers m,n we have Tm=1n and Tn=1m, then Tmn =