Ruudukko

var v = parseInt(process.argv[0]);
if (isNaN(v)) v = parseInt(process.argv[1]);
if (isNaN(v)) v = parseInt(process.argv[2]);
if (isNaN(v)) v = parseInt(process.argv[3]);
if (isNaN(v)) v = parseInt(process.argv[4]);
if (isNaN(v)) v = parseInt(process.argv[5]);
if (isNaN(v)) v = parseInt(process.argv[6]);

var div = v / 2;
if (v % 2 !== 0) {
	div += 0.5;
}

var posses = [];
for (var y = 0; y < v; y++) {
	posses[y] = [];
}

for (var y = 0; y < v; y++) {
	for (var x = 0; x < v; x++) {
		if (x == y) {
			add(x, y, '1');
		} else if (x == v - y - 1) {
			add(x, y, v.toString());
		} else {
			add(x, y, 'x');
		}
	}
}

var amounts = div - 1;
for (var index = 1; index < amounts + 1; index++) {
	var amount = v - index * 2;

	for (var y = 0; y < amount + 1; y += amount) {
		for (var x = 0; x < amount; x++) {
			var realIndex = x + index;

			if (y == 0) {
				add(realIndex, index - 1, (realIndex + 1).toString());
			} else {
				add(realIndex, v - index, (v - realIndex).toString());
			}
		}
	}

	for (var y = 0; y < amount + 1; y += amount) {
		for (var x = 0; x < amount; x++) {
			var realIndex = x + index;

			if (y == 0) {
				add(index - 1, realIndex, (realIndex + 1).toString());
			} else {
				add(v - index, realIndex, (v - realIndex).toString());
			}
		}
	}
}

for (var y = 0; y < v; y++) {
	var str = '';
	for (var x = 0; x < v; x++) {
		str += posses[y][x] + ' ';
	}
	console.log(sub(str));
}

function add(x, y, str) {
	posses[y][x] = str;
}

function sub(str) {
	return str.substring(0, str.length);
}

Test 1

Verdict: WRONG ANSWER

Test 2

Verdict: WRONG ANSWER

Test 3

Verdict: WRONG ANSWER

Test 4

Verdict: WRONG ANSWER

Test 5

Verdict: WRONG ANSWER

Test 6

Verdict: WRONG ANSWER