Yep, I misread it also: I saw j = 2 * i (which would do evens and then odds when NUMBER is odd, or evens then evens again if NUMBER is even).
For what it really is - powers of 2 mod NUMBER - when NUMBER is large most reads should be out of the cache. So the first example has to read from main memory only every 64th index, and the second example has to read from main memory on almost every read. I think this agrees with what you are saying. This also explains why it is ~5x slower, which seemed too large from my previous understanding.
For what it really is - powers of 2 mod NUMBER - when NUMBER is large most reads should be out of the cache. So the first example has to read from main memory only every 64th index, and the second example has to read from main memory on almost every read. I think this agrees with what you are saying. This also explains why it is ~5x slower, which seemed too large from my previous understanding.