Find the smallest positive integer for which
Solution
Dividing both sides by , we obtain Factorials are small at first, so we can rule out some small cases: when , the left hand side is , which is much smaller than . (Similar calculations show that through do not work. either.) Setting , the left-hand side is 288 , which is still smaller than . However, gives , so 8 is the smallest integer for which the inequality holds.
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