Database BASIC ALGEBRAIC STRUCTURES Groups Abelian groups Group sum operation gsumcl  
				
		 
		
			
		 
		Description:   Closure of a finite group sum.  (Contributed by Mario Carneiro , 15-Dec-2014)   (Revised by Mario Carneiro , 24-Apr-2016)   (Revised by AV , 3-Jun-2019) 
		
			
				
					Ref 
					Expression 
				 
					
						Hypotheses 
						gsumcl.b   ⊢   B  =  Base  G      
					 
					
						gsumcl.z   ⊢   0  ˙ =  0  G      
					 
					
						gsumcl.g    ⊢   φ   →   G  ∈  CMnd         
					 
					
						gsumcl.a    ⊢   φ   →   A  ∈  V         
					 
					
						gsumcl.f    ⊢   φ   →   F  :  A  ⟶  B         
					 
					
						gsumcl.w    ⊢   φ   →  finSupp  0  ˙ ⁡  F      
					 
				
					Assertion 
					gsumcl    ⊢   φ   →   ∑  G F ∈  B         
				 
			
		 
		
				Proof 
				
					
						Step 
						Hyp 
						Ref 
						Expression 
					 
						
							1 
								
							 
							gsumcl.b  ⊢   B  =  Base  G      
						
							2 
								
							 
							gsumcl.z  ⊢   0  ˙ =  0  G      
						
							3 
								
							 
							gsumcl.g   ⊢   φ   →   G  ∈  CMnd         
						
							4 
								
							 
							gsumcl.a   ⊢   φ   →   A  ∈  V         
						
							5 
								
							 
							gsumcl.f   ⊢   φ   →   F  :  A  ⟶  B         
						
							6 
								
							 
							gsumcl.w   ⊢   φ   →  finSupp  0  ˙ ⁡  F      
						
							7 
								6 
							 
							fsuppimpd   ⊢   φ   →   F  supp  0  ˙ ∈  Fin         
						
							8 
								1  2  3  4  5  7 
							 
							gsumcl2   ⊢   φ   →   ∑  G F ∈  B