[1,2,3,4,11,12,13,14,21,22,23,24,31,32,33,34,41, 42,43,44,111,112,113,114,121,122,123,124,131,132, 133,134,141,142,143,144,211,212,213,214,221,222, 223,224,231,232,233,234,241,242,243,244,311,312, 313,314,321]