$output = [ 
[ 1, 2, 5, 6, 9 ],
[ 1, 3, 5, 6, 9 ],
[ 1, 4, 5, 6, 9 ],
[ 1, 2, 5, 7, 9 ],
[ 1, 3, 5, 7, 9 ],

... and so on