It consists of five numbers: 1, 3, 4, 5, 6.
This is the arrangement of 4 out of 5. There are 5×4×3×2= 120 kinds of * *.
Four digits consisting of the last four digits: (only one group, others for your reference)
1345, 1346, 1354, 1356, 1364, 1365,
1435, 1436, 1453, 1456, 1463, 1465,
1534, 1536, 1543, 1546, 1563, 1564,
1634, 1635, 1643, 1645, 1653, 1654,
……
Adding 92 to all four digits is the specific number of 120.