#include <stdio.h>
//練習問題E
int tri(int T){
if(T==0)
return 0;
if(T==1)
return 0;
if(T==2)
return 1;
else
return tri(T-1)+tri(T-2)+tri(T-3);
}
int main(void) {
int n = 7;
printf("数列Tnについて, n=%dのときの値は%d\n", n
, tri
(n
)); return 0;
}
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