eval5

var result = [];

function fibonacci(n, res) {
    var a = 1,
        b = 1,
        sum;
    for (var i = 0; i < n; i++) {
        res.push(a);
        sum = a + b;
        a = b;
        b = sum;
    }
}
fibonacci(12, result);
result.join(', ');
Console: