A conjecture, related to the prime sieve list length.

function primes = Sieve(x)
primes = 2;
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for i=1:x
vi = primes(end)+1:2*max(primes);

for j=1:i
vi = vi((vi/primes(j)-floor(vi/primes(j)))~=0);
end

primes = [primes vi];
end
feature accel off

end

Related to finding a good way to preallocate for the prime list. 

 

Probably will convert the values to strings and stick them in a cell array with an approximately appropriate reallocated length, and then just get rid of empty cells.

I would use it for x>6,
rather, x>=6