The original example of PCM mainframes was the Amdahl 470 mainframe computer which was plug - compatible with the IBM System 360 and 370 , costing millions of dollars to develop .
Head entity: 370 Q1586139 23
Tail entity: ibm system 360 Q609843 19 20 21
Relation (head \u2192 tail): P155
Inverse relation (tail \u2192 head): P156