AMR10F.cpp

/*
USER: zobayer
TASK: AMR10F
ALGO: math
*/

#include <cstdio>
using namespace std;

int main() {
	int t, n, a, d;
	scanf("%d", &t);
	while(t--) {
		scanf("%d%d%d", &n, &a, &d);
		printf("%d\n", n*(2*a + (n-1)*d) / 2);
	}
	return 0;
}