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Estimate of a combination number by another
Task number: 3854
Estimate (2m+1m) from both sides by a function of (2mm).
Solution
From Pascal’s triangle we have (2m+1m)=(2mm)+(2mm+1), while (2mm)>(2mm+1)>0.
Then straightforwardly.
Answer
The desired estimate could be e.g. (2mm)<(2m+1m)<2(2mm).
