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  1. #include <stdio.h>
  2. //a{n} = -6a{n-1} -9a{n-2}, a{1}=1, a{2}=2(再帰なし版)
  3.  
  4. int main(void) {
  5. 	int a,b=1,c=2;
  6. 	int n=4;
  7. 	for (int i=3;i<=n;i++){
  8. 		a=-6*c-9*b;
  9. 		b=c;
  10. 		c=a;
  11. 	}
  12.  
  13.  
  14.     printf("数列a%dの値は%d\n", n, a);
  15. 	return 0;
  16. }
  17.  
  18.  
Success #stdin #stdout 0s 5276KB
comments (?)
stdin 
Standard input is empty
stdout 
数列a4の値は108
https://ideone.com/J5XhfC
language:
C (gcc 8.3)
created:
72 days ago
visibility:
public

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