async + closure

async_closure.js

var _ = require('underscore'),
    async = require('async');

var funcs = [];

for(var i=0; i<56; i++){
    funcs.push(
        (function(index){
            return function(cb){

                cb(null, index);
            }

        })(i)

    );

}

async.parallel( funcs, function(err, results){
    console.log(results);
});