Execute Node.js Online

		function mul(a, b, p)
		{
			return (a*b)%p
		}
		function div(a, b, p)
		{
			while(a < 0)
				a += p

			while(b < 0)
				b += p

			for(var i = 0; i<p; ++i)
				if(mul(i, b, p) == a)
					return i
		}
		function EllipticCurve(a, b, p)
		{
			return {
				a: a % p,
				b: b % p,
				p: p
			}
		}
		function PointOnEllipticCcurve(curve, x, y)
		{
			return (x*x*x + curve.a*x + curve.b - y*y) % curve.p == 0
		}
		function EllipticCurvePoints(curve)
		{
			var points = []

			for(var i=0; i<curve.p; ++i)
				for(var j=0; j<curve.p; ++j)
					if(PointOnEllipticCurve(curve, i, j))
						points.push({x: i, y: j})

			return points
		}
		function AddEllipticPoint(curve, p1, p2)
		{
			var s

			if(p1.is_null)
				return p2

			if(p2.is_null)
				return p1
			if(p1.x != p2.x)
			{
				s = div(p1.y - p2.y, p1.x - p2.x, curve.p)
				var p_x = (s*s - p1.x -p2.x) % curve.p

				return {
					x: p_x,
					y: (-p1.y + s*(p1.x - p_x)) % curve.p
				} 
			}
			if(p1.y == p2.y)
			{
				s = div((3 * p1.x*p1.x + curve.a)%curve.p, 2*p1.y % curve.p, curve.p)
				var p_x = (s*s - 2*p1.x) % curve.p
				return {
					x: p_x,
					y: (-p1.y + s*(p1.x - p_x))%curve.p
				}
			}
			return {
				x:       0,
				y:       0,
				is_null: true
			}
		}
		function NormalizePoint(curve, p)
		{
			while(p.x < 0)
				p.x += curve.p

			while(p.y < 0)
				p.y += curve.p

			return p
		}
		var curve = EllipticCurve(-1, 188, 751)
		function nP(curve, point, n)
		{
			var p1 = {x: point.x, y: point.y}
			var p2 = {x: point.x, y: point.y}

			for(var i=0; i<n - 1; ++i)
			{
				p1 = AddEllipticPoint(curve, p1, p2)
				NormalizePoint(curve, p1)
			}
			return p1
		}
		
		console.log( nP(curve, {x: 0, y: 250}, 260))