Hey Gene ---- your math here is only partially correct. Or, perhaps it is more accurate to say that its accuracy depends on exactly what you mean.
If the odds against hitting any on particular number are 37-1, it is true that these odds hold for each individual spin of the wheel. Thus, on the first spin, the odds against hitting say 13 are 37-1. Then, whether 13 comes up or not on the first spin, the odds against hitting 13 on the second spin are 37-1. And on the 3rd, 37-1. And so on, forever.
HOWEVER, looking at a series of spins (either from up front to determine the probability that the event will occur or after the fact to determine the probability that it would have occurred), the odds against hitting A PARTICULAR NUMBER (say 13 again) twice in a row is 37x37 = 1369 to 1. The odds against hitting 13 three times in a row are 37x37x37 = 50,653 to 1. The odds against hitting 13 twelve times in a row are 37 to the 12th power to 1 (astronomically large or roughly 6,250,000,000,000,000,000,000,000 to 1).
In short, while the odds ARE exactly the same for each spin, they ARE NOT the same when it comes to hitting A PARTICULAR NUMBER two or more times in a row.
----- jim o\-S