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## 'Helen's Conjecture' printed from http://nrich.maths.org/

Helen made the conjecture that "every multiple of six has more
factors than the two numbers either side of it". Is this conjecture
true?

For example, the third multiple of 6 is 18 which has six factors
(counting 1 and 18), while 17 and 19, the numbers on each side of
it, have two each being prime.