I just want to point out that shared_ptr needs more book keeping
(reference counter). So, you'd have two allocated memory blocks, the
ref counter and the array itself. This memory layout is very similar
to the layout you get by writing

   auto sv = make_shared<vector<T>>(n);

on any decent implementation that would allocate the sizeof(vector<T>)
bytes together with the ref counting book keeping bits. You're just
getting an an additional level of indirection if you access vector
elements via sv. Though, You can avoid this using the vector's
iterators for a loop. So, what I'm saying is that I see little reason
to prefer sharedptr<T> with an array deleter over a
shared_ptr<vector<T>>.

Cheers!
SG