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var mods_predefined = [
	[4, 0, 0, 3, 5, 1, 3, 6, 2, 4, 0, 2],
	[5, 1, 1, 4, 6, 2, 4, 0, 3, 5, 1, 3],
	[6, 2, 2, 5, 0, 3, 5, 1, 4, 6, 2, 4],
	[0, 3, 4, 0, 2, 5, 0, 3, 6, 1, 4, 6],
	[2, 5, 5, 1, 3, 6, 1, 4, 0, 2, 5, 0],
	[3, 6, 6, 2, 4, 0, 2, 5, 1, 3, 6, 1],
	[4, 0, 0, 3, 5, 1, 3, 6, 2, 4, 0, 2],
	[5, 1, 2, 5, 0, 3, 5, 1, 4, 6, 2, 4],
	[0, 3, 3, 6, 1, 4, 6, 2, 5, 0, 3, 5],
	[1, 4, 4, 0, 2, 5, 0, 3, 6, 1, 4, 6],
	[2, 5, 5, 1, 3, 6, 1, 4, 0, 2, 5, 0],
	[3, 6, 0, 3, 5, 1, 3, 6, 2, 4, 0, 2],
	[5, 1, 1, 4, 6, 2, 4, 0, 3, 5, 1, 3],
	[6, 2, 2, 5, 0, 3, 5, 1, 4, 6, 2, 4],
	[0, 3, 3, 6, 1, 4, 6, 2, 5, 0, 3, 5],
	[1, 4, 5, 1, 3, 6, 1, 4, 0, 2, 5, 0],
	[3, 6, 6, 2, 4, 0, 2, 5, 1, 3, 6, 1],
	[4, 0, 0, 3, 5, 1, 3, 6, 2, 4, 0, 2],
	[5, 1, 1, 4, 6, 2, 4, 0, 3, 5, 1, 3],
	[6, 2, 3, 6, 1, 4, 6, 2, 5, 0, 3, 5],
	[1, 4, 4, 0, 2, 5, 0, 3, 6, 1, 4, 6],
	[2, 5, 5, 1, 3, 6, 1, 4, 0, 2, 5, 0],
	[3, 6, 6, 2, 4, 0, 2, 5, 1, 3, 6, 1],
	[4, 0, 1, 4, 6, 2, 4, 0, 3, 5, 1, 3],
	[6, 2, 2, 5, 0, 3, 5, 1, 4, 6, 2, 4],
	[0, 3, 3, 6, 1, 4, 6, 2, 5, 0, 3, 5],
	[1, 4, 4, 0, 2, 5, 0, 3, 6, 1, 4, 6],
	[2, 5, 6, 2, 4, 0, 2, 5, 1, 3, 6, 1],
];

	var mods = [
		new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12), new Array(12)
	];

function get_mods(){
	var year = 2016-7;
	var month = 1;
	
	for(year; year<(2016-7+28); year++){
		for(month; month<=12; month++){
			var day = 1;
			var date = new Date(year, month-1, day);
			var temp = date.getDay();
			
			
			var i = (year + 7) % 28
			var j = (month-1) % 12;
						
			mods[i][j] = ( temp + 5 * 7 - day + 1 ) % 7;
		}
		month = 1;
	}
	console.log((a = mods.toString(), b = mods_predefined.toString(),...