Why 39? And why is 39 used for two locations, A and B? Several numbers are skipped. Why did they number launch pads like they did?

39 was used for Space Shuttle launches Slc-14=Mercury Atlas; Slc-19=Gemini; Slc-34=Apollo's 1 & 7; Slc-37=Delta IV; Slc-40=SpaceX Falcon; Slc-41=Atlas V; Lc-39A SpaceX Heavy; Lc-39B SLS Rocket (old Space Shuttle launch pad) Not sure why missing pads or A/B, hey, its the "gubbermint" thought I'd give you some additional information. Numbers increase from South to North

Thanks, Jules. I knew about the Shuttles, but not the rest. You gave me my thing-to-learn of the day 😁. From south to north, at least on Google Maps, I'm seeing: 29, 25, 5, 6, then what might be 13 or so that don't show a number, then the renamed landing pad #1, 14, 15, another 2 unnumbered, 20, 34, 37, 40, 41, 39A, and 39B. I'm confused.