#include <stdio.h>
 
// 課題3で作成した再帰関数をそのまま利用
int rec_kadai3(int n){
    if (n == 0) return 3;
    else if (n == 1) return 0;
    else if (n == 2) return 2;
    else return rec_kadai3(n - 2) + rec_kadai3(n - 3); 
}
 
int main(void) {
    int max_n = 50; // 50項まで調べる
    int an;
 
    printf("課題4: a[n]がnで割り切れるときのnの値:\n");
 
    // n=1からmax_nまで調べる
    for (int n = 1; n <= max_n; n++) {
        an = rec_kadai3(n);
 
        // if文を用いて、(a[n] % n == 0) を満たすか判定
        if (an % n == 0) {
            printf("n = %d (a[%d] = %d)\n", n, n, an);
        }
    }
 
    return 0;
}

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