| Numar natural prim sau compus? | 
		        
			        | Proposed by 
        batranetupetre  | 
		        
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			                    | (2 comments) | 1.819 times displayed |  |  |  
			                    | Numarul A= (2^2010+1)/2665  este prim sau compus? |  
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				                | 2665=5*13*412^2010+1=(2^10)201 +1=1024^201=(1025-1)^201 +1=(25*41-1)^201+1=M25-1+1=M25
 2^2010+1=(2^10)201 +1=1024^201=(1025-1)^201 +1=(25*41-1)^201+1=M41-1+1=M41
 2^2010 +1=(2^6)^335+1=64^335 +1=(65-1)^335+1=M13-1+1=M13
 Prin urmare numaratorul se divide cu 25, 13 si 41 deci A este numar natural si cum numitorul se divide cu 5 dar nu cu 25, A se divide cu 5, deci este numar compus.
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