I *think* the 12 and 13 were the YF-12/YF-13, which later became the SR-71.
As for the others...
Your guess is as good as mine. The number scheme got a little weird around Vietnam. Part of the problem was two different number schemes. The Air Force planes went clear up to F-106 (the Air Force's new 'F' series, used for every jet fighter except for the original P-80). Meanwhile, the Navy, had always used the 'F' designator for its planes. The original F-4, for example, was a prop plane which was used in the Battle of Midway.
At some point during Vietnam, somebody evidently decided to start over again and enforce a uniform numbering system. I'm not sure what came between F-4 (the Phantom II) and YF-12 (mentioned above), however.
As for the others...
Your guess is as good as mine. The number scheme got a little weird around Vietnam. Part of the problem was two different number schemes. The Air Force planes went clear up to F-106 (the Air Force's new 'F' series, used for every jet fighter except for the original P-80). Meanwhile, the Navy, had always used the 'F' designator for its planes. The original F-4, for example, was a prop plane which was used in the Battle of Midway.
At some point during Vietnam, somebody evidently decided to start over again and enforce a uniform numbering system. I'm not sure what came between F-4 (the Phantom II) and YF-12 (mentioned above), however.