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hi,
could anyone help me with the following problem?
find the number of pairs (x,y) for which 1<=x,y<=10^7 and gcd(x,y) = x xor y
here are my thoughts: we can let x=da and y=db for coprime a,b then we must have a XOR b = 1 i.e. a and b are consecutive integers. how do we proceed from here
thanks!
sorry :(
here
thank you so much!
probably $$$O(n ~log~ n)$$$ soln
oops i miscalculated, apparently da xor db does not necessarily equal d(a xor b). thanks for the help though
seems no solution lower than $$$O(n\log n)$$$?