24 has 3 as a factor. 3 is one less than a power of 2.

freehorse 6 days ago | parent | next [-]

Well n=21 too but the solution for n=15 used that 15 is one less than a power of 2, not its divisors, because we are living in modulo n.

	▲	oh_my_goodness 6 days ago \| parent [-]
		Thanks. I don't understand quantum computing at all.

Dylan16807 6 days ago | parent | prev [-]

That's a bit off, but more importantly using information about the answer to make the circuit cheaper is cheating.