In support of my argument (which is admittedly a fine-point), I offer this example.
In a std::vector, is it always true that every element 0 to size()-1, is a valid constructed object?
I say the answer is yes.
In a regular C++ array (not std::array<T,N>), is it true that each object is a valid constructed object? Not necessarily.
Is that a sequence? All the elements in the middle are undefined. Now maybe std::array<T,N> default-construct each element, thus making it a sequence. But I meant arrays in general.
int *foo = new int;
int = 1;
int = 100;
Opps, I meant to use malloc(100 * sizeof(int)), not operator new. I say malloc because often a container will separate allocation of memory from object construction. I just think that to be a logical sequence, each element must be defined (as in constructed), in addition to the standard mathematical definition of a sequence.